Merge branch 'overlayfs.v25' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs into for-linus
This commit is contained in:
Al Viro
commit
1be47b387a
|
|
@ -67,6 +67,7 @@ prototypes:
|
|||
struct file *, unsigned open_flag,
|
||||
umode_t create_mode, int *opened);
|
||||
int (*tmpfile) (struct inode *, struct dentry *, umode_t);
|
||||
int (*dentry_open)(struct dentry *, struct file *, const struct cred *);
|
||||
|
||||
locking rules:
|
||||
all may block
|
||||
|
|
@ -96,6 +97,7 @@ fiemap: no
|
|||
update_time: no
|
||||
atomic_open: yes
|
||||
tmpfile: no
|
||||
dentry_open: no
|
||||
|
||||
Additionally, ->rmdir(), ->unlink() and ->rename() have ->i_mutex on
|
||||
victim.
|
||||
|
|
|
|||
|
|
@ -0,0 +1,198 @@
|
|||
Written by: Neil Brown <neilb@suse.de>
|
||||
|
||||
Overlay Filesystem
|
||||
==================
|
||||
|
||||
This document describes a prototype for a new approach to providing
|
||||
overlay-filesystem functionality in Linux (sometimes referred to as
|
||||
union-filesystems). An overlay-filesystem tries to present a
|
||||
filesystem which is the result over overlaying one filesystem on top
|
||||
of the other.
|
||||
|
||||
The result will inevitably fail to look exactly like a normal
|
||||
filesystem for various technical reasons. The expectation is that
|
||||
many use cases will be able to ignore these differences.
|
||||
|
||||
This approach is 'hybrid' because the objects that appear in the
|
||||
filesystem do not all appear to belong to that filesystem. In many
|
||||
cases an object accessed in the union will be indistinguishable
|
||||
from accessing the corresponding object from the original filesystem.
|
||||
This is most obvious from the 'st_dev' field returned by stat(2).
|
||||
|
||||
While directories will report an st_dev from the overlay-filesystem,
|
||||
all non-directory objects will report an st_dev from the lower or
|
||||
upper filesystem that is providing the object. Similarly st_ino will
|
||||
only be unique when combined with st_dev, and both of these can change
|
||||
over the lifetime of a non-directory object. Many applications and
|
||||
tools ignore these values and will not be affected.
|
||||
|
||||
Upper and Lower
|
||||
---------------
|
||||
|
||||
An overlay filesystem combines two filesystems - an 'upper' filesystem
|
||||
and a 'lower' filesystem. When a name exists in both filesystems, the
|
||||
object in the 'upper' filesystem is visible while the object in the
|
||||
'lower' filesystem is either hidden or, in the case of directories,
|
||||
merged with the 'upper' object.
|
||||
|
||||
It would be more correct to refer to an upper and lower 'directory
|
||||
tree' rather than 'filesystem' as it is quite possible for both
|
||||
directory trees to be in the same filesystem and there is no
|
||||
requirement that the root of a filesystem be given for either upper or
|
||||
lower.
|
||||
|
||||
The lower filesystem can be any filesystem supported by Linux and does
|
||||
not need to be writable. The lower filesystem can even be another
|
||||
overlayfs. The upper filesystem will normally be writable and if it
|
||||
is it must support the creation of trusted.* extended attributes, and
|
||||
must provide valid d_type in readdir responses, so NFS is not suitable.
|
||||
|
||||
A read-only overlay of two read-only filesystems may use any
|
||||
filesystem type.
|
||||
|
||||
Directories
|
||||
-----------
|
||||
|
||||
Overlaying mainly involves directories. If a given name appears in both
|
||||
upper and lower filesystems and refers to a non-directory in either,
|
||||
then the lower object is hidden - the name refers only to the upper
|
||||
object.
|
||||
|
||||
Where both upper and lower objects are directories, a merged directory
|
||||
is formed.
|
||||
|
||||
At mount time, the two directories given as mount options "lowerdir" and
|
||||
"upperdir" are combined into a merged directory:
|
||||
|
||||
mount -t overlayfs overlayfs -olowerdir=/lower,upperdir=/upper,\
|
||||
workdir=/work /merged
|
||||
|
||||
The "workdir" needs to be an empty directory on the same filesystem
|
||||
as upperdir.
|
||||
|
||||
Then whenever a lookup is requested in such a merged directory, the
|
||||
lookup is performed in each actual directory and the combined result
|
||||
is cached in the dentry belonging to the overlay filesystem. If both
|
||||
actual lookups find directories, both are stored and a merged
|
||||
directory is created, otherwise only one is stored: the upper if it
|
||||
exists, else the lower.
|
||||
|
||||
Only the lists of names from directories are merged. Other content
|
||||
such as metadata and extended attributes are reported for the upper
|
||||
directory only. These attributes of the lower directory are hidden.
|
||||
|
||||
whiteouts and opaque directories
|
||||
--------------------------------
|
||||
|
||||
In order to support rm and rmdir without changing the lower
|
||||
filesystem, an overlay filesystem needs to record in the upper filesystem
|
||||
that files have been removed. This is done using whiteouts and opaque
|
||||
directories (non-directories are always opaque).
|
||||
|
||||
A whiteout is created as a character device with 0/0 device number.
|
||||
When a whiteout is found in the upper level of a merged directory, any
|
||||
matching name in the lower level is ignored, and the whiteout itself
|
||||
is also hidden.
|
||||
|
||||
A directory is made opaque by setting the xattr "trusted.overlay.opaque"
|
||||
to "y". Where the upper filesystem contains an opaque directory, any
|
||||
directory in the lower filesystem with the same name is ignored.
|
||||
|
||||
readdir
|
||||
-------
|
||||
|
||||
When a 'readdir' request is made on a merged directory, the upper and
|
||||
lower directories are each read and the name lists merged in the
|
||||
obvious way (upper is read first, then lower - entries that already
|
||||
exist are not re-added). This merged name list is cached in the
|
||||
'struct file' and so remains as long as the file is kept open. If the
|
||||
directory is opened and read by two processes at the same time, they
|
||||
will each have separate caches. A seekdir to the start of the
|
||||
directory (offset 0) followed by a readdir will cause the cache to be
|
||||
discarded and rebuilt.
|
||||
|
||||
This means that changes to the merged directory do not appear while a
|
||||
directory is being read. This is unlikely to be noticed by many
|
||||
programs.
|
||||
|
||||
seek offsets are assigned sequentially when the directories are read.
|
||||
Thus if
|
||||
- read part of a directory
|
||||
- remember an offset, and close the directory
|
||||
- re-open the directory some time later
|
||||
- seek to the remembered offset
|
||||
|
||||
there may be little correlation between the old and new locations in
|
||||
the list of filenames, particularly if anything has changed in the
|
||||
directory.
|
||||
|
||||
Readdir on directories that are not merged is simply handled by the
|
||||
underlying directory (upper or lower).
|
||||
|
||||
|
||||
Non-directories
|
||||
---------------
|
||||
|
||||
Objects that are not directories (files, symlinks, device-special
|
||||
files etc.) are presented either from the upper or lower filesystem as
|
||||
appropriate. When a file in the lower filesystem is accessed in a way
|
||||
the requires write-access, such as opening for write access, changing
|
||||
some metadata etc., the file is first copied from the lower filesystem
|
||||
to the upper filesystem (copy_up). Note that creating a hard-link
|
||||
also requires copy_up, though of course creation of a symlink does
|
||||
not.
|
||||
|
||||
The copy_up may turn out to be unnecessary, for example if the file is
|
||||
opened for read-write but the data is not modified.
|
||||
|
||||
The copy_up process first makes sure that the containing directory
|
||||
exists in the upper filesystem - creating it and any parents as
|
||||
necessary. It then creates the object with the same metadata (owner,
|
||||
mode, mtime, symlink-target etc.) and then if the object is a file, the
|
||||
data is copied from the lower to the upper filesystem. Finally any
|
||||
extended attributes are copied up.
|
||||
|
||||
Once the copy_up is complete, the overlay filesystem simply
|
||||
provides direct access to the newly created file in the upper
|
||||
filesystem - future operations on the file are barely noticed by the
|
||||
overlay filesystem (though an operation on the name of the file such as
|
||||
rename or unlink will of course be noticed and handled).
|
||||
|
||||
|
||||
Non-standard behavior
|
||||
---------------------
|
||||
|
||||
The copy_up operation essentially creates a new, identical file and
|
||||
moves it over to the old name. The new file may be on a different
|
||||
filesystem, so both st_dev and st_ino of the file may change.
|
||||
|
||||
Any open files referring to this inode will access the old data and
|
||||
metadata. Similarly any file locks obtained before copy_up will not
|
||||
apply to the copied up file.
|
||||
|
||||
On a file opened with O_RDONLY fchmod(2), fchown(2), futimesat(2) and
|
||||
fsetxattr(2) will fail with EROFS.
|
||||
|
||||
If a file with multiple hard links is copied up, then this will
|
||||
"break" the link. Changes will not be propagated to other names
|
||||
referring to the same inode.
|
||||
|
||||
Symlinks in /proc/PID/ and /proc/PID/fd which point to a non-directory
|
||||
object in overlayfs will not contain valid absolute paths, only
|
||||
relative paths leading up to the filesystem's root. This will be
|
||||
fixed in the future.
|
||||
|
||||
Some operations are not atomic, for example a crash during copy_up or
|
||||
rename will leave the filesystem in an inconsistent state. This will
|
||||
be addressed in the future.
|
||||
|
||||
Changes to underlying filesystems
|
||||
---------------------------------
|
||||
|
||||
Offline changes, when the overlay is not mounted, are allowed to either
|
||||
the upper or the lower trees.
|
||||
|
||||
Changes to the underlying filesystems while part of a mounted overlay
|
||||
filesystem are not allowed. If the underlying filesystem is changed,
|
||||
the behavior of the overlay is undefined, though it will not result in
|
||||
a crash or deadlock.
|
||||
|
|
@ -364,6 +364,7 @@ struct inode_operations {
|
|||
int (*atomic_open)(struct inode *, struct dentry *, struct file *,
|
||||
unsigned open_flag, umode_t create_mode, int *opened);
|
||||
int (*tmpfile) (struct inode *, struct dentry *, umode_t);
|
||||
int (*dentry_open)(struct dentry *, struct file *, const struct cred *);
|
||||
};
|
||||
|
||||
Again, all methods are called without any locks being held, unless
|
||||
|
|
@ -696,6 +697,12 @@ struct address_space_operations {
|
|||
but instead uses bmap to find out where the blocks in the file
|
||||
are and uses those addresses directly.
|
||||
|
||||
dentry_open: *WARNING: probably going away soon, do not use!* This is an
|
||||
alternative to f_op->open(), the difference is that this method may open
|
||||
a file not necessarily originating from the same filesystem as the one
|
||||
i_op->open() was called on. It may be useful for stacking filesystems
|
||||
which want to allow native I/O directly on underlying files.
|
||||
|
||||
|
||||
invalidatepage: If a page has PagePrivate set, then invalidatepage
|
||||
will be called when part or all of the page is to be removed
|
||||
|
|
|
|||
|
|
@ -6832,6 +6832,13 @@ F: drivers/scsi/osd/
|
|||
F: include/scsi/osd_*
|
||||
F: fs/exofs/
|
||||
|
||||
OVERLAYFS FILESYSTEM
|
||||
M: Miklos Szeredi <miklos@szeredi.hu>
|
||||
L: linux-fsdevel@vger.kernel.org
|
||||
S: Supported
|
||||
F: fs/overlayfs/*
|
||||
F: Documentation/filesystems/overlayfs.txt
|
||||
|
||||
P54 WIRELESS DRIVER
|
||||
M: Christian Lamparter <chunkeey@googlemail.com>
|
||||
L: linux-wireless@vger.kernel.org
|
||||
|
|
|
|||
|
|
@ -67,6 +67,7 @@ source "fs/quota/Kconfig"
|
|||
|
||||
source "fs/autofs4/Kconfig"
|
||||
source "fs/fuse/Kconfig"
|
||||
source "fs/overlayfs/Kconfig"
|
||||
|
||||
menu "Caches"
|
||||
|
||||
|
|
|
|||
|
|
@ -104,6 +104,7 @@ obj-$(CONFIG_QNX6FS_FS) += qnx6/
|
|||
obj-$(CONFIG_AUTOFS4_FS) += autofs4/
|
||||
obj-$(CONFIG_ADFS_FS) += adfs/
|
||||
obj-$(CONFIG_FUSE_FS) += fuse/
|
||||
obj-$(CONFIG_OVERLAYFS_FS) += overlayfs/
|
||||
obj-$(CONFIG_UDF_FS) += udf/
|
||||
obj-$(CONFIG_SUN_OPENPROMFS) += openpromfs/
|
||||
obj-$(CONFIG_OMFS_FS) += omfs/
|
||||
|
|
|
|||
|
|
@ -765,23 +765,6 @@ out:
|
|||
return ret;
|
||||
}
|
||||
|
||||
/* copy of check_sticky in fs/namei.c()
|
||||
* It's inline, so penalty for filesystems that don't use sticky bit is
|
||||
* minimal.
|
||||
*/
|
||||
static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
|
||||
{
|
||||
kuid_t fsuid = current_fsuid();
|
||||
|
||||
if (!(dir->i_mode & S_ISVTX))
|
||||
return 0;
|
||||
if (uid_eq(inode->i_uid, fsuid))
|
||||
return 0;
|
||||
if (uid_eq(dir->i_uid, fsuid))
|
||||
return 0;
|
||||
return !capable(CAP_FOWNER);
|
||||
}
|
||||
|
||||
/* copy of may_delete in fs/namei.c()
|
||||
* Check whether we can remove a link victim from directory dir, check
|
||||
* whether the type of victim is right.
|
||||
|
|
@ -817,8 +800,7 @@ static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
|
|||
return error;
|
||||
if (IS_APPEND(dir))
|
||||
return -EPERM;
|
||||
if (btrfs_check_sticky(dir, victim->d_inode)||
|
||||
IS_APPEND(victim->d_inode)||
|
||||
if (check_sticky(dir, victim->d_inode) || IS_APPEND(victim->d_inode) ||
|
||||
IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
|
||||
return -EPERM;
|
||||
if (isdir) {
|
||||
|
|
|
|||
|
|
@ -566,6 +566,13 @@ static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags
|
|||
s->s_maxbytes = path.dentry->d_sb->s_maxbytes;
|
||||
s->s_blocksize = path.dentry->d_sb->s_blocksize;
|
||||
s->s_magic = ECRYPTFS_SUPER_MAGIC;
|
||||
s->s_stack_depth = path.dentry->d_sb->s_stack_depth + 1;
|
||||
|
||||
rc = -EINVAL;
|
||||
if (s->s_stack_depth > FILESYSTEM_MAX_STACK_DEPTH) {
|
||||
pr_err("eCryptfs: maximum fs stacking depth exceeded\n");
|
||||
goto out_free;
|
||||
}
|
||||
|
||||
inode = ecryptfs_get_inode(path.dentry->d_inode, s);
|
||||
rc = PTR_ERR(inode);
|
||||
|
|
|
|||
|
|
@ -3190,6 +3190,39 @@ static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent)
|
|||
}
|
||||
}
|
||||
|
||||
static struct inode *ext4_whiteout_for_rename(struct ext4_renament *ent,
|
||||
int credits, handle_t **h)
|
||||
{
|
||||
struct inode *wh;
|
||||
handle_t *handle;
|
||||
int retries = 0;
|
||||
|
||||
/*
|
||||
* for inode block, sb block, group summaries,
|
||||
* and inode bitmap
|
||||
*/
|
||||
credits += (EXT4_MAXQUOTAS_TRANS_BLOCKS(ent->dir->i_sb) +
|
||||
EXT4_XATTR_TRANS_BLOCKS + 4);
|
||||
retry:
|
||||
wh = ext4_new_inode_start_handle(ent->dir, S_IFCHR | WHITEOUT_MODE,
|
||||
&ent->dentry->d_name, 0, NULL,
|
||||
EXT4_HT_DIR, credits);
|
||||
|
||||
handle = ext4_journal_current_handle();
|
||||
if (IS_ERR(wh)) {
|
||||
if (handle)
|
||||
ext4_journal_stop(handle);
|
||||
if (PTR_ERR(wh) == -ENOSPC &&
|
||||
ext4_should_retry_alloc(ent->dir->i_sb, &retries))
|
||||
goto retry;
|
||||
} else {
|
||||
*h = handle;
|
||||
init_special_inode(wh, wh->i_mode, WHITEOUT_DEV);
|
||||
wh->i_op = &ext4_special_inode_operations;
|
||||
}
|
||||
return wh;
|
||||
}
|
||||
|
||||
/*
|
||||
* Anybody can rename anything with this: the permission checks are left to the
|
||||
* higher-level routines.
|
||||
|
|
@ -3199,7 +3232,8 @@ static void ext4_update_dir_count(handle_t *handle, struct ext4_renament *ent)
|
|||
* This comes from rename(const char *oldpath, const char *newpath)
|
||||
*/
|
||||
static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
|
||||
struct inode *new_dir, struct dentry *new_dentry)
|
||||
struct inode *new_dir, struct dentry *new_dentry,
|
||||
unsigned int flags)
|
||||
{
|
||||
handle_t *handle = NULL;
|
||||
struct ext4_renament old = {
|
||||
|
|
@ -3214,6 +3248,9 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
|
|||
};
|
||||
int force_reread;
|
||||
int retval;
|
||||
struct inode *whiteout = NULL;
|
||||
int credits;
|
||||
u8 old_file_type;
|
||||
|
||||
dquot_initialize(old.dir);
|
||||
dquot_initialize(new.dir);
|
||||
|
|
@ -3252,11 +3289,17 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
|
|||
if (new.inode && !test_opt(new.dir->i_sb, NO_AUTO_DA_ALLOC))
|
||||
ext4_alloc_da_blocks(old.inode);
|
||||
|
||||
handle = ext4_journal_start(old.dir, EXT4_HT_DIR,
|
||||
(2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
|
||||
EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2));
|
||||
if (IS_ERR(handle))
|
||||
return PTR_ERR(handle);
|
||||
credits = (2 * EXT4_DATA_TRANS_BLOCKS(old.dir->i_sb) +
|
||||
EXT4_INDEX_EXTRA_TRANS_BLOCKS + 2);
|
||||
if (!(flags & RENAME_WHITEOUT)) {
|
||||
handle = ext4_journal_start(old.dir, EXT4_HT_DIR, credits);
|
||||
if (IS_ERR(handle))
|
||||
return PTR_ERR(handle);
|
||||
} else {
|
||||
whiteout = ext4_whiteout_for_rename(&old, credits, &handle);
|
||||
if (IS_ERR(whiteout))
|
||||
return PTR_ERR(whiteout);
|
||||
}
|
||||
|
||||
if (IS_DIRSYNC(old.dir) || IS_DIRSYNC(new.dir))
|
||||
ext4_handle_sync(handle);
|
||||
|
|
@ -3284,13 +3327,26 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
|
|||
*/
|
||||
force_reread = (new.dir->i_ino == old.dir->i_ino &&
|
||||
ext4_test_inode_flag(new.dir, EXT4_INODE_INLINE_DATA));
|
||||
|
||||
old_file_type = old.de->file_type;
|
||||
if (whiteout) {
|
||||
/*
|
||||
* Do this before adding a new entry, so the old entry is sure
|
||||
* to be still pointing to the valid old entry.
|
||||
*/
|
||||
retval = ext4_setent(handle, &old, whiteout->i_ino,
|
||||
EXT4_FT_CHRDEV);
|
||||
if (retval)
|
||||
goto end_rename;
|
||||
ext4_mark_inode_dirty(handle, whiteout);
|
||||
}
|
||||
if (!new.bh) {
|
||||
retval = ext4_add_entry(handle, new.dentry, old.inode);
|
||||
if (retval)
|
||||
goto end_rename;
|
||||
} else {
|
||||
retval = ext4_setent(handle, &new,
|
||||
old.inode->i_ino, old.de->file_type);
|
||||
old.inode->i_ino, old_file_type);
|
||||
if (retval)
|
||||
goto end_rename;
|
||||
}
|
||||
|
|
@ -3305,10 +3361,12 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
|
|||
old.inode->i_ctime = ext4_current_time(old.inode);
|
||||
ext4_mark_inode_dirty(handle, old.inode);
|
||||
|
||||
/*
|
||||
* ok, that's it
|
||||
*/
|
||||
ext4_rename_delete(handle, &old, force_reread);
|
||||
if (!whiteout) {
|
||||
/*
|
||||
* ok, that's it
|
||||
*/
|
||||
ext4_rename_delete(handle, &old, force_reread);
|
||||
}
|
||||
|
||||
if (new.inode) {
|
||||
ext4_dec_count(handle, new.inode);
|
||||
|
|
@ -3344,6 +3402,12 @@ end_rename:
|
|||
brelse(old.dir_bh);
|
||||
brelse(old.bh);
|
||||
brelse(new.bh);
|
||||
if (whiteout) {
|
||||
if (retval)
|
||||
drop_nlink(whiteout);
|
||||
unlock_new_inode(whiteout);
|
||||
iput(whiteout);
|
||||
}
|
||||
if (handle)
|
||||
ext4_journal_stop(handle);
|
||||
return retval;
|
||||
|
|
@ -3476,18 +3540,15 @@ static int ext4_rename2(struct inode *old_dir, struct dentry *old_dentry,
|
|||
struct inode *new_dir, struct dentry *new_dentry,
|
||||
unsigned int flags)
|
||||
{
|
||||
if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
|
||||
if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
|
||||
return -EINVAL;
|
||||
|
||||
if (flags & RENAME_EXCHANGE) {
|
||||
return ext4_cross_rename(old_dir, old_dentry,
|
||||
new_dir, new_dentry);
|
||||
}
|
||||
/*
|
||||
* Existence checking was done by the VFS, otherwise "RENAME_NOREPLACE"
|
||||
* is equivalent to regular rename.
|
||||
*/
|
||||
return ext4_rename(old_dir, old_dentry, new_dir, new_dentry);
|
||||
|
||||
return ext4_rename(old_dir, old_dentry, new_dir, new_dentry, flags);
|
||||
}
|
||||
|
||||
/*
|
||||
|
|
|
|||
|
|
@ -47,7 +47,6 @@ extern void __init chrdev_init(void);
|
|||
/*
|
||||
* namei.c
|
||||
*/
|
||||
extern int __inode_permission(struct inode *, int);
|
||||
extern int user_path_mountpoint_at(int, const char __user *, unsigned int, struct path *);
|
||||
extern int vfs_path_lookup(struct dentry *, struct vfsmount *,
|
||||
const char *, unsigned int, struct path *);
|
||||
|
|
@ -138,12 +137,6 @@ extern long prune_dcache_sb(struct super_block *sb, unsigned long nr_to_scan,
|
|||
*/
|
||||
extern int rw_verify_area(int, struct file *, const loff_t *, size_t);
|
||||
|
||||
/*
|
||||
* splice.c
|
||||
*/
|
||||
extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
|
||||
loff_t *opos, size_t len, unsigned int flags);
|
||||
|
||||
/*
|
||||
* pipe.c
|
||||
*/
|
||||
|
|
|
|||
41
fs/namei.c
41
fs/namei.c
|
|
@ -416,6 +416,7 @@ int __inode_permission(struct inode *inode, int mask)
|
|||
|
||||
return security_inode_permission(inode, mask);
|
||||
}
|
||||
EXPORT_SYMBOL(__inode_permission);
|
||||
|
||||
/**
|
||||
* sb_permission - Check superblock-level permissions
|
||||
|
|
@ -2383,22 +2384,17 @@ kern_path_mountpoint(int dfd, const char *name, struct path *path,
|
|||
}
|
||||
EXPORT_SYMBOL(kern_path_mountpoint);
|
||||
|
||||
/*
|
||||
* It's inline, so penalty for filesystems that don't use sticky bit is
|
||||
* minimal.
|
||||
*/
|
||||
static inline int check_sticky(struct inode *dir, struct inode *inode)
|
||||
int __check_sticky(struct inode *dir, struct inode *inode)
|
||||
{
|
||||
kuid_t fsuid = current_fsuid();
|
||||
|
||||
if (!(dir->i_mode & S_ISVTX))
|
||||
return 0;
|
||||
if (uid_eq(inode->i_uid, fsuid))
|
||||
return 0;
|
||||
if (uid_eq(dir->i_uid, fsuid))
|
||||
return 0;
|
||||
return !capable_wrt_inode_uidgid(inode, CAP_FOWNER);
|
||||
}
|
||||
EXPORT_SYMBOL(__check_sticky);
|
||||
|
||||
/*
|
||||
* Check whether we can remove a link victim from directory dir, check
|
||||
|
|
@ -3064,9 +3060,12 @@ finish_open_created:
|
|||
error = may_open(&nd->path, acc_mode, open_flag);
|
||||
if (error)
|
||||
goto out;
|
||||
file->f_path.mnt = nd->path.mnt;
|
||||
error = finish_open(file, nd->path.dentry, NULL, opened);
|
||||
if (error) {
|
||||
|
||||
BUG_ON(*opened & FILE_OPENED); /* once it's opened, it's opened */
|
||||
error = vfs_open(&nd->path, file, current_cred());
|
||||
if (!error) {
|
||||
*opened |= FILE_OPENED;
|
||||
} else {
|
||||
if (error == -EOPENSTALE)
|
||||
goto stale_open;
|
||||
goto out;
|
||||
|
|
@ -4210,12 +4209,16 @@ SYSCALL_DEFINE5(renameat2, int, olddfd, const char __user *, oldname,
|
|||
bool should_retry = false;
|
||||
int error;
|
||||
|
||||
if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
|
||||
if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
|
||||
return -EINVAL;
|
||||
|
||||
if ((flags & RENAME_NOREPLACE) && (flags & RENAME_EXCHANGE))
|
||||
if ((flags & (RENAME_NOREPLACE | RENAME_WHITEOUT)) &&
|
||||
(flags & RENAME_EXCHANGE))
|
||||
return -EINVAL;
|
||||
|
||||
if ((flags & RENAME_WHITEOUT) && !capable(CAP_MKNOD))
|
||||
return -EPERM;
|
||||
|
||||
retry:
|
||||
from = user_path_parent(olddfd, oldname, &oldnd, lookup_flags);
|
||||
if (IS_ERR(from)) {
|
||||
|
|
@ -4347,6 +4350,20 @@ SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newna
|
|||
return sys_renameat2(AT_FDCWD, oldname, AT_FDCWD, newname, 0);
|
||||
}
|
||||
|
||||
int vfs_whiteout(struct inode *dir, struct dentry *dentry)
|
||||
{
|
||||
int error = may_create(dir, dentry);
|
||||
if (error)
|
||||
return error;
|
||||
|
||||
if (!dir->i_op->mknod)
|
||||
return -EPERM;
|
||||
|
||||
return dir->i_op->mknod(dir, dentry,
|
||||
S_IFCHR | WHITEOUT_MODE, WHITEOUT_DEV);
|
||||
}
|
||||
EXPORT_SYMBOL(vfs_whiteout);
|
||||
|
||||
int readlink_copy(char __user *buffer, int buflen, const char *link)
|
||||
{
|
||||
int len = PTR_ERR(link);
|
||||
|
|
|
|||
|
|
@ -1686,6 +1686,33 @@ void drop_collected_mounts(struct vfsmount *mnt)
|
|||
namespace_unlock();
|
||||
}
|
||||
|
||||
/**
|
||||
* clone_private_mount - create a private clone of a path
|
||||
*
|
||||
* This creates a new vfsmount, which will be the clone of @path. The new will
|
||||
* not be attached anywhere in the namespace and will be private (i.e. changes
|
||||
* to the originating mount won't be propagated into this).
|
||||
*
|
||||
* Release with mntput().
|
||||
*/
|
||||
struct vfsmount *clone_private_mount(struct path *path)
|
||||
{
|
||||
struct mount *old_mnt = real_mount(path->mnt);
|
||||
struct mount *new_mnt;
|
||||
|
||||
if (IS_MNT_UNBINDABLE(old_mnt))
|
||||
return ERR_PTR(-EINVAL);
|
||||
|
||||
down_read(&namespace_sem);
|
||||
new_mnt = clone_mnt(old_mnt, path->dentry, CL_PRIVATE);
|
||||
up_read(&namespace_sem);
|
||||
if (IS_ERR(new_mnt))
|
||||
return ERR_CAST(new_mnt);
|
||||
|
||||
return &new_mnt->mnt;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(clone_private_mount);
|
||||
|
||||
int iterate_mounts(int (*f)(struct vfsmount *, void *), void *arg,
|
||||
struct vfsmount *root)
|
||||
{
|
||||
|
|
|
|||
23
fs/open.c
23
fs/open.c
|
|
@ -823,8 +823,7 @@ struct file *dentry_open(const struct path *path, int flags,
|
|||
f = get_empty_filp();
|
||||
if (!IS_ERR(f)) {
|
||||
f->f_flags = flags;
|
||||
f->f_path = *path;
|
||||
error = do_dentry_open(f, NULL, cred);
|
||||
error = vfs_open(path, f, cred);
|
||||
if (!error) {
|
||||
/* from now on we need fput() to dispose of f */
|
||||
error = open_check_o_direct(f);
|
||||
|
|
@ -841,6 +840,26 @@ struct file *dentry_open(const struct path *path, int flags,
|
|||
}
|
||||
EXPORT_SYMBOL(dentry_open);
|
||||
|
||||
/**
|
||||
* vfs_open - open the file at the given path
|
||||
* @path: path to open
|
||||
* @filp: newly allocated file with f_flag initialized
|
||||
* @cred: credentials to use
|
||||
*/
|
||||
int vfs_open(const struct path *path, struct file *filp,
|
||||
const struct cred *cred)
|
||||
{
|
||||
struct inode *inode = path->dentry->d_inode;
|
||||
|
||||
if (inode->i_op->dentry_open)
|
||||
return inode->i_op->dentry_open(path->dentry, filp, cred);
|
||||
else {
|
||||
filp->f_path = *path;
|
||||
return do_dentry_open(filp, NULL, cred);
|
||||
}
|
||||
}
|
||||
EXPORT_SYMBOL(vfs_open);
|
||||
|
||||
static inline int build_open_flags(int flags, umode_t mode, struct open_flags *op)
|
||||
{
|
||||
int lookup_flags = 0;
|
||||
|
|
|
|||
|
|
@ -0,0 +1,10 @@
|
|||
config OVERLAYFS_FS
|
||||
tristate "Overlay filesystem support"
|
||||
help
|
||||
An overlay filesystem combines two filesystems - an 'upper' filesystem
|
||||
and a 'lower' filesystem. When a name exists in both filesystems, the
|
||||
object in the 'upper' filesystem is visible while the object in the
|
||||
'lower' filesystem is either hidden or, in the case of directories,
|
||||
merged with the 'upper' object.
|
||||
|
||||
For more information see Documentation/filesystems/overlayfs.txt
|
||||
|
|
@ -0,0 +1,7 @@
|
|||
#
|
||||
# Makefile for the overlay filesystem.
|
||||
#
|
||||
|
||||
obj-$(CONFIG_OVERLAYFS_FS) += overlayfs.o
|
||||
|
||||
overlayfs-objs := super.o inode.o dir.o readdir.o copy_up.o
|
||||
|
|
@ -0,0 +1,414 @@
|
|||
/*
|
||||
*
|
||||
* Copyright (C) 2011 Novell Inc.
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify it
|
||||
* under the terms of the GNU General Public License version 2 as published by
|
||||
* the Free Software Foundation.
|
||||
*/
|
||||
|
||||
#include <linux/fs.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/file.h>
|
||||
#include <linux/splice.h>
|
||||
#include <linux/xattr.h>
|
||||
#include <linux/security.h>
|
||||
#include <linux/uaccess.h>
|
||||
#include <linux/sched.h>
|
||||
#include <linux/namei.h>
|
||||
#include "overlayfs.h"
|
||||
|
||||
#define OVL_COPY_UP_CHUNK_SIZE (1 << 20)
|
||||
|
||||
int ovl_copy_xattr(struct dentry *old, struct dentry *new)
|
||||
{
|
||||
ssize_t list_size, size;
|
||||
char *buf, *name, *value;
|
||||
int error;
|
||||
|
||||
if (!old->d_inode->i_op->getxattr ||
|
||||
!new->d_inode->i_op->getxattr)
|
||||
return 0;
|
||||
|
||||
list_size = vfs_listxattr(old, NULL, 0);
|
||||
if (list_size <= 0) {
|
||||
if (list_size == -EOPNOTSUPP)
|
||||
return 0;
|
||||
return list_size;
|
||||
}
|
||||
|
||||
buf = kzalloc(list_size, GFP_KERNEL);
|
||||
if (!buf)
|
||||
return -ENOMEM;
|
||||
|
||||
error = -ENOMEM;
|
||||
value = kmalloc(XATTR_SIZE_MAX, GFP_KERNEL);
|
||||
if (!value)
|
||||
goto out;
|
||||
|
||||
list_size = vfs_listxattr(old, buf, list_size);
|
||||
if (list_size <= 0) {
|
||||
error = list_size;
|
||||
goto out_free_value;
|
||||
}
|
||||
|
||||
for (name = buf; name < (buf + list_size); name += strlen(name) + 1) {
|
||||
size = vfs_getxattr(old, name, value, XATTR_SIZE_MAX);
|
||||
if (size <= 0) {
|
||||
error = size;
|
||||
goto out_free_value;
|
||||
}
|
||||
error = vfs_setxattr(new, name, value, size, 0);
|
||||
if (error)
|
||||
goto out_free_value;
|
||||
}
|
||||
|
||||
out_free_value:
|
||||
kfree(value);
|
||||
out:
|
||||
kfree(buf);
|
||||
return error;
|
||||
}
|
||||
|
||||
static int ovl_copy_up_data(struct path *old, struct path *new, loff_t len)
|
||||
{
|
||||
struct file *old_file;
|
||||
struct file *new_file;
|
||||
loff_t old_pos = 0;
|
||||
loff_t new_pos = 0;
|
||||
int error = 0;
|
||||
|
||||
if (len == 0)
|
||||
return 0;
|
||||
|
||||
old_file = ovl_path_open(old, O_RDONLY);
|
||||
if (IS_ERR(old_file))
|
||||
return PTR_ERR(old_file);
|
||||
|
||||
new_file = ovl_path_open(new, O_WRONLY);
|
||||
if (IS_ERR(new_file)) {
|
||||
error = PTR_ERR(new_file);
|
||||
goto out_fput;
|
||||
}
|
||||
|
||||
/* FIXME: copy up sparse files efficiently */
|
||||
while (len) {
|
||||
size_t this_len = OVL_COPY_UP_CHUNK_SIZE;
|
||||
long bytes;
|
||||
|
||||
if (len < this_len)
|
||||
this_len = len;
|
||||
|
||||
if (signal_pending_state(TASK_KILLABLE, current)) {
|
||||
error = -EINTR;
|
||||
break;
|
||||
}
|
||||
|
||||
bytes = do_splice_direct(old_file, &old_pos,
|
||||
new_file, &new_pos,
|
||||
this_len, SPLICE_F_MOVE);
|
||||
if (bytes <= 0) {
|
||||
error = bytes;
|
||||
break;
|
||||
}
|
||||
WARN_ON(old_pos != new_pos);
|
||||
|
||||
len -= bytes;
|
||||
}
|
||||
|
||||
fput(new_file);
|
||||
out_fput:
|
||||
fput(old_file);
|
||||
return error;
|
||||
}
|
||||
|
||||
static char *ovl_read_symlink(struct dentry *realdentry)
|
||||
{
|
||||
int res;
|
||||
char *buf;
|
||||
struct inode *inode = realdentry->d_inode;
|
||||
mm_segment_t old_fs;
|
||||
|
||||
res = -EINVAL;
|
||||
if (!inode->i_op->readlink)
|
||||
goto err;
|
||||
|
||||
res = -ENOMEM;
|
||||
buf = (char *) __get_free_page(GFP_KERNEL);
|
||||
if (!buf)
|
||||
goto err;
|
||||
|
||||
old_fs = get_fs();
|
||||
set_fs(get_ds());
|
||||
/* The cast to a user pointer is valid due to the set_fs() */
|
||||
res = inode->i_op->readlink(realdentry,
|
||||
(char __user *)buf, PAGE_SIZE - 1);
|
||||
set_fs(old_fs);
|
||||
if (res < 0) {
|
||||
free_page((unsigned long) buf);
|
||||
goto err;
|
||||
}
|
||||
buf[res] = '\0';
|
||||
|
||||
return buf;
|
||||
|
||||
err:
|
||||
return ERR_PTR(res);
|
||||
}
|
||||
|
||||
static int ovl_set_timestamps(struct dentry *upperdentry, struct kstat *stat)
|
||||
{
|
||||
struct iattr attr = {
|
||||
.ia_valid =
|
||||
ATTR_ATIME | ATTR_MTIME | ATTR_ATIME_SET | ATTR_MTIME_SET,
|
||||
.ia_atime = stat->atime,
|
||||
.ia_mtime = stat->mtime,
|
||||
};
|
||||
|
||||
return notify_change(upperdentry, &attr, NULL);
|
||||
}
|
||||
|
||||
int ovl_set_attr(struct dentry *upperdentry, struct kstat *stat)
|
||||
{
|
||||
int err = 0;
|
||||
|
||||
if (!S_ISLNK(stat->mode)) {
|
||||
struct iattr attr = {
|
||||
.ia_valid = ATTR_MODE,
|
||||
.ia_mode = stat->mode,
|
||||
};
|
||||
err = notify_change(upperdentry, &attr, NULL);
|
||||
}
|
||||
if (!err) {
|
||||
struct iattr attr = {
|
||||
.ia_valid = ATTR_UID | ATTR_GID,
|
||||
.ia_uid = stat->uid,
|
||||
.ia_gid = stat->gid,
|
||||
};
|
||||
err = notify_change(upperdentry, &attr, NULL);
|
||||
}
|
||||
if (!err)
|
||||
ovl_set_timestamps(upperdentry, stat);
|
||||
|
||||
return err;
|
||||
|
||||
}
|
||||
|
||||
static int ovl_copy_up_locked(struct dentry *workdir, struct dentry *upperdir,
|
||||
struct dentry *dentry, struct path *lowerpath,
|
||||
struct kstat *stat, struct iattr *attr,
|
||||
const char *link)
|
||||
{
|
||||
struct inode *wdir = workdir->d_inode;
|
||||
struct inode *udir = upperdir->d_inode;
|
||||
struct dentry *newdentry = NULL;
|
||||
struct dentry *upper = NULL;
|
||||
umode_t mode = stat->mode;
|
||||
int err;
|
||||
|
||||
newdentry = ovl_lookup_temp(workdir, dentry);
|
||||
err = PTR_ERR(newdentry);
|
||||
if (IS_ERR(newdentry))
|
||||
goto out;
|
||||
|
||||
upper = lookup_one_len(dentry->d_name.name, upperdir,
|
||||
dentry->d_name.len);
|
||||
err = PTR_ERR(upper);
|
||||
if (IS_ERR(upper))
|
||||
goto out1;
|
||||
|
||||
/* Can't properly set mode on creation because of the umask */
|
||||
stat->mode &= S_IFMT;
|
||||
err = ovl_create_real(wdir, newdentry, stat, link, NULL, true);
|
||||
stat->mode = mode;
|
||||
if (err)
|
||||
goto out2;
|
||||
|
||||
if (S_ISREG(stat->mode)) {
|
||||
struct path upperpath;
|
||||
ovl_path_upper(dentry, &upperpath);
|
||||
BUG_ON(upperpath.dentry != NULL);
|
||||
upperpath.dentry = newdentry;
|
||||
|
||||
err = ovl_copy_up_data(lowerpath, &upperpath, stat->size);
|
||||
if (err)
|
||||
goto out_cleanup;
|
||||
}
|
||||
|
||||
err = ovl_copy_xattr(lowerpath->dentry, newdentry);
|
||||
if (err)
|
||||
goto out_cleanup;
|
||||
|
||||
mutex_lock(&newdentry->d_inode->i_mutex);
|
||||
err = ovl_set_attr(newdentry, stat);
|
||||
if (!err && attr)
|
||||
err = notify_change(newdentry, attr, NULL);
|
||||
mutex_unlock(&newdentry->d_inode->i_mutex);
|
||||
if (err)
|
||||
goto out_cleanup;
|
||||
|
||||
err = ovl_do_rename(wdir, newdentry, udir, upper, 0);
|
||||
if (err)
|
||||
goto out_cleanup;
|
||||
|
||||
ovl_dentry_update(dentry, newdentry);
|
||||
newdentry = NULL;
|
||||
|
||||
/*
|
||||
* Non-directores become opaque when copied up.
|
||||
*/
|
||||
if (!S_ISDIR(stat->mode))
|
||||
ovl_dentry_set_opaque(dentry, true);
|
||||
out2:
|
||||
dput(upper);
|
||||
out1:
|
||||
dput(newdentry);
|
||||
out:
|
||||
return err;
|
||||
|
||||
out_cleanup:
|
||||
ovl_cleanup(wdir, newdentry);
|
||||
goto out;
|
||||
}
|
||||
|
||||
/*
|
||||
* Copy up a single dentry
|
||||
*
|
||||
* Directory renames only allowed on "pure upper" (already created on
|
||||
* upper filesystem, never copied up). Directories which are on lower or
|
||||
* are merged may not be renamed. For these -EXDEV is returned and
|
||||
* userspace has to deal with it. This means, when copying up a
|
||||
* directory we can rely on it and ancestors being stable.
|
||||
*
|
||||
* Non-directory renames start with copy up of source if necessary. The
|
||||
* actual rename will only proceed once the copy up was successful. Copy
|
||||
* up uses upper parent i_mutex for exclusion. Since rename can change
|
||||
* d_parent it is possible that the copy up will lock the old parent. At
|
||||
* that point the file will have already been copied up anyway.
|
||||
*/
|
||||
int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry,
|
||||
struct path *lowerpath, struct kstat *stat,
|
||||
struct iattr *attr)
|
||||
{
|
||||
struct dentry *workdir = ovl_workdir(dentry);
|
||||
int err;
|
||||
struct kstat pstat;
|
||||
struct path parentpath;
|
||||
struct dentry *upperdir;
|
||||
struct dentry *upperdentry;
|
||||
const struct cred *old_cred;
|
||||
struct cred *override_cred;
|
||||
char *link = NULL;
|
||||
|
||||
ovl_path_upper(parent, &parentpath);
|
||||
upperdir = parentpath.dentry;
|
||||
|
||||
err = vfs_getattr(&parentpath, &pstat);
|
||||
if (err)
|
||||
return err;
|
||||
|
||||
if (S_ISLNK(stat->mode)) {
|
||||
link = ovl_read_symlink(lowerpath->dentry);
|
||||
if (IS_ERR(link))
|
||||
return PTR_ERR(link);
|
||||
}
|
||||
|
||||
err = -ENOMEM;
|
||||
override_cred = prepare_creds();
|
||||
if (!override_cred)
|
||||
goto out_free_link;
|
||||
|
||||
override_cred->fsuid = stat->uid;
|
||||
override_cred->fsgid = stat->gid;
|
||||
/*
|
||||
* CAP_SYS_ADMIN for copying up extended attributes
|
||||
* CAP_DAC_OVERRIDE for create
|
||||
* CAP_FOWNER for chmod, timestamp update
|
||||
* CAP_FSETID for chmod
|
||||
* CAP_CHOWN for chown
|
||||
* CAP_MKNOD for mknod
|
||||
*/
|
||||
cap_raise(override_cred->cap_effective, CAP_SYS_ADMIN);
|
||||
cap_raise(override_cred->cap_effective, CAP_DAC_OVERRIDE);
|
||||
cap_raise(override_cred->cap_effective, CAP_FOWNER);
|
||||
cap_raise(override_cred->cap_effective, CAP_FSETID);
|
||||
cap_raise(override_cred->cap_effective, CAP_CHOWN);
|
||||
cap_raise(override_cred->cap_effective, CAP_MKNOD);
|
||||
old_cred = override_creds(override_cred);
|
||||
|
||||
err = -EIO;
|
||||
if (lock_rename(workdir, upperdir) != NULL) {
|
||||
pr_err("overlayfs: failed to lock workdir+upperdir\n");
|
||||
goto out_unlock;
|
||||
}
|
||||
upperdentry = ovl_dentry_upper(dentry);
|
||||
if (upperdentry) {
|
||||
unlock_rename(workdir, upperdir);
|
||||
err = 0;
|
||||
/* Raced with another copy-up? Do the setattr here */
|
||||
if (attr) {
|
||||
mutex_lock(&upperdentry->d_inode->i_mutex);
|
||||
err = notify_change(upperdentry, attr, NULL);
|
||||
mutex_unlock(&upperdentry->d_inode->i_mutex);
|
||||
}
|
||||
goto out_put_cred;
|
||||
}
|
||||
|
||||
err = ovl_copy_up_locked(workdir, upperdir, dentry, lowerpath,
|
||||
stat, attr, link);
|
||||
if (!err) {
|
||||
/* Restore timestamps on parent (best effort) */
|
||||
ovl_set_timestamps(upperdir, &pstat);
|
||||
}
|
||||
out_unlock:
|
||||
unlock_rename(workdir, upperdir);
|
||||
out_put_cred:
|
||||
revert_creds(old_cred);
|
||||
put_cred(override_cred);
|
||||
|
||||
out_free_link:
|
||||
if (link)
|
||||
free_page((unsigned long) link);
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
int ovl_copy_up(struct dentry *dentry)
|
||||
{
|
||||
int err;
|
||||
|
||||
err = 0;
|
||||
while (!err) {
|
||||
struct dentry *next;
|
||||
struct dentry *parent;
|
||||
struct path lowerpath;
|
||||
struct kstat stat;
|
||||
enum ovl_path_type type = ovl_path_type(dentry);
|
||||
|
||||
if (type != OVL_PATH_LOWER)
|
||||
break;
|
||||
|
||||
next = dget(dentry);
|
||||
/* find the topmost dentry not yet copied up */
|
||||
for (;;) {
|
||||
parent = dget_parent(next);
|
||||
|
||||
type = ovl_path_type(parent);
|
||||
if (type != OVL_PATH_LOWER)
|
||||
break;
|
||||
|
||||
dput(next);
|
||||
next = parent;
|
||||
}
|
||||
|
||||
ovl_path_lower(next, &lowerpath);
|
||||
err = vfs_getattr(&lowerpath, &stat);
|
||||
if (!err)
|
||||
err = ovl_copy_up_one(parent, next, &lowerpath, &stat, NULL);
|
||||
|
||||
dput(parent);
|
||||
dput(next);
|
||||
}
|
||||
|
||||
return err;
|
||||
}
|
||||
|
|
@ -0,0 +1,921 @@
|
|||
/*
|
||||
*
|
||||
* Copyright (C) 2011 Novell Inc.
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify it
|
||||
* under the terms of the GNU General Public License version 2 as published by
|
||||
* the Free Software Foundation.
|
||||
*/
|
||||
|
||||
#include <linux/fs.h>
|
||||
#include <linux/namei.h>
|
||||
#include <linux/xattr.h>
|
||||
#include <linux/security.h>
|
||||
#include <linux/cred.h>
|
||||
#include "overlayfs.h"
|
||||
|
||||
void ovl_cleanup(struct inode *wdir, struct dentry *wdentry)
|
||||
{
|
||||
int err;
|
||||
|
||||
dget(wdentry);
|
||||
if (S_ISDIR(wdentry->d_inode->i_mode))
|
||||
err = ovl_do_rmdir(wdir, wdentry);
|
||||
else
|
||||
err = ovl_do_unlink(wdir, wdentry);
|
||||
dput(wdentry);
|
||||
|
||||
if (err) {
|
||||
pr_err("overlayfs: cleanup of '%pd2' failed (%i)\n",
|
||||
wdentry, err);
|
||||
}
|
||||
}
|
||||
|
||||
struct dentry *ovl_lookup_temp(struct dentry *workdir, struct dentry *dentry)
|
||||
{
|
||||
struct dentry *temp;
|
||||
char name[20];
|
||||
|
||||
snprintf(name, sizeof(name), "#%lx", (unsigned long) dentry);
|
||||
|
||||
temp = lookup_one_len(name, workdir, strlen(name));
|
||||
if (!IS_ERR(temp) && temp->d_inode) {
|
||||
pr_err("overlayfs: workdir/%s already exists\n", name);
|
||||
dput(temp);
|
||||
temp = ERR_PTR(-EIO);
|
||||
}
|
||||
|
||||
return temp;
|
||||
}
|
||||
|
||||
/* caller holds i_mutex on workdir */
|
||||
static struct dentry *ovl_whiteout(struct dentry *workdir,
|
||||
struct dentry *dentry)
|
||||
{
|
||||
int err;
|
||||
struct dentry *whiteout;
|
||||
struct inode *wdir = workdir->d_inode;
|
||||
|
||||
whiteout = ovl_lookup_temp(workdir, dentry);
|
||||
if (IS_ERR(whiteout))
|
||||
return whiteout;
|
||||
|
||||
err = ovl_do_whiteout(wdir, whiteout);
|
||||
if (err) {
|
||||
dput(whiteout);
|
||||
whiteout = ERR_PTR(err);
|
||||
}
|
||||
|
||||
return whiteout;
|
||||
}
|
||||
|
||||
int ovl_create_real(struct inode *dir, struct dentry *newdentry,
|
||||
struct kstat *stat, const char *link,
|
||||
struct dentry *hardlink, bool debug)
|
||||
{
|
||||
int err;
|
||||
|
||||
if (newdentry->d_inode)
|
||||
return -ESTALE;
|
||||
|
||||
if (hardlink) {
|
||||
err = ovl_do_link(hardlink, dir, newdentry, debug);
|
||||
} else {
|
||||
switch (stat->mode & S_IFMT) {
|
||||
case S_IFREG:
|
||||
err = ovl_do_create(dir, newdentry, stat->mode, debug);
|
||||
break;
|
||||
|
||||
case S_IFDIR:
|
||||
err = ovl_do_mkdir(dir, newdentry, stat->mode, debug);
|
||||
break;
|
||||
|
||||
case S_IFCHR:
|
||||
case S_IFBLK:
|
||||
case S_IFIFO:
|
||||
case S_IFSOCK:
|
||||
err = ovl_do_mknod(dir, newdentry,
|
||||
stat->mode, stat->rdev, debug);
|
||||
break;
|
||||
|
||||
case S_IFLNK:
|
||||
err = ovl_do_symlink(dir, newdentry, link, debug);
|
||||
break;
|
||||
|
||||
default:
|
||||
err = -EPERM;
|
||||
}
|
||||
}
|
||||
if (!err && WARN_ON(!newdentry->d_inode)) {
|
||||
/*
|
||||
* Not quite sure if non-instantiated dentry is legal or not.
|
||||
* VFS doesn't seem to care so check and warn here.
|
||||
*/
|
||||
err = -ENOENT;
|
||||
}
|
||||
return err;
|
||||
}
|
||||
|
||||
static int ovl_set_opaque(struct dentry *upperdentry)
|
||||
{
|
||||
return ovl_do_setxattr(upperdentry, ovl_opaque_xattr, "y", 1, 0);
|
||||
}
|
||||
|
||||
static void ovl_remove_opaque(struct dentry *upperdentry)
|
||||
{
|
||||
int err;
|
||||
|
||||
err = ovl_do_removexattr(upperdentry, ovl_opaque_xattr);
|
||||
if (err) {
|
||||
pr_warn("overlayfs: failed to remove opaque from '%s' (%i)\n",
|
||||
upperdentry->d_name.name, err);
|
||||
}
|
||||
}
|
||||
|
||||
static int ovl_dir_getattr(struct vfsmount *mnt, struct dentry *dentry,
|
||||
struct kstat *stat)
|
||||
{
|
||||
int err;
|
||||
enum ovl_path_type type;
|
||||
struct path realpath;
|
||||
|
||||
type = ovl_path_real(dentry, &realpath);
|
||||
err = vfs_getattr(&realpath, stat);
|
||||
if (err)
|
||||
return err;
|
||||
|
||||
stat->dev = dentry->d_sb->s_dev;
|
||||
stat->ino = dentry->d_inode->i_ino;
|
||||
|
||||
/*
|
||||
* It's probably not worth it to count subdirs to get the
|
||||
* correct link count. nlink=1 seems to pacify 'find' and
|
||||
* other utilities.
|
||||
*/
|
||||
if (type == OVL_PATH_MERGE)
|
||||
stat->nlink = 1;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int ovl_create_upper(struct dentry *dentry, struct inode *inode,
|
||||
struct kstat *stat, const char *link,
|
||||
struct dentry *hardlink)
|
||||
{
|
||||
struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
|
||||
struct inode *udir = upperdir->d_inode;
|
||||
struct dentry *newdentry;
|
||||
int err;
|
||||
|
||||
mutex_lock_nested(&udir->i_mutex, I_MUTEX_PARENT);
|
||||
newdentry = lookup_one_len(dentry->d_name.name, upperdir,
|
||||
dentry->d_name.len);
|
||||
err = PTR_ERR(newdentry);
|
||||
if (IS_ERR(newdentry))
|
||||
goto out_unlock;
|
||||
err = ovl_create_real(udir, newdentry, stat, link, hardlink, false);
|
||||
if (err)
|
||||
goto out_dput;
|
||||
|
||||
ovl_dentry_version_inc(dentry->d_parent);
|
||||
ovl_dentry_update(dentry, newdentry);
|
||||
ovl_copyattr(newdentry->d_inode, inode);
|
||||
d_instantiate(dentry, inode);
|
||||
newdentry = NULL;
|
||||
out_dput:
|
||||
dput(newdentry);
|
||||
out_unlock:
|
||||
mutex_unlock(&udir->i_mutex);
|
||||
return err;
|
||||
}
|
||||
|
||||
static int ovl_lock_rename_workdir(struct dentry *workdir,
|
||||
struct dentry *upperdir)
|
||||
{
|
||||
/* Workdir should not be the same as upperdir */
|
||||
if (workdir == upperdir)
|
||||
goto err;
|
||||
|
||||
/* Workdir should not be subdir of upperdir and vice versa */
|
||||
if (lock_rename(workdir, upperdir) != NULL)
|
||||
goto err_unlock;
|
||||
|
||||
return 0;
|
||||
|
||||
err_unlock:
|
||||
unlock_rename(workdir, upperdir);
|
||||
err:
|
||||
pr_err("overlayfs: failed to lock workdir+upperdir\n");
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
static struct dentry *ovl_clear_empty(struct dentry *dentry,
|
||||
struct list_head *list)
|
||||
{
|
||||
struct dentry *workdir = ovl_workdir(dentry);
|
||||
struct inode *wdir = workdir->d_inode;
|
||||
struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
|
||||
struct inode *udir = upperdir->d_inode;
|
||||
struct path upperpath;
|
||||
struct dentry *upper;
|
||||
struct dentry *opaquedir;
|
||||
struct kstat stat;
|
||||
int err;
|
||||
|
||||
err = ovl_lock_rename_workdir(workdir, upperdir);
|
||||
if (err)
|
||||
goto out;
|
||||
|
||||
ovl_path_upper(dentry, &upperpath);
|
||||
err = vfs_getattr(&upperpath, &stat);
|
||||
if (err)
|
||||
goto out_unlock;
|
||||
|
||||
err = -ESTALE;
|
||||
if (!S_ISDIR(stat.mode))
|
||||
goto out_unlock;
|
||||
upper = upperpath.dentry;
|
||||
if (upper->d_parent->d_inode != udir)
|
||||
goto out_unlock;
|
||||
|
||||
opaquedir = ovl_lookup_temp(workdir, dentry);
|
||||
err = PTR_ERR(opaquedir);
|
||||
if (IS_ERR(opaquedir))
|
||||
goto out_unlock;
|
||||
|
||||
err = ovl_create_real(wdir, opaquedir, &stat, NULL, NULL, true);
|
||||
if (err)
|
||||
goto out_dput;
|
||||
|
||||
err = ovl_copy_xattr(upper, opaquedir);
|
||||
if (err)
|
||||
goto out_cleanup;
|
||||
|
||||
err = ovl_set_opaque(opaquedir);
|
||||
if (err)
|
||||
goto out_cleanup;
|
||||
|
||||
mutex_lock(&opaquedir->d_inode->i_mutex);
|
||||
err = ovl_set_attr(opaquedir, &stat);
|
||||
mutex_unlock(&opaquedir->d_inode->i_mutex);
|
||||
if (err)
|
||||
goto out_cleanup;
|
||||
|
||||
err = ovl_do_rename(wdir, opaquedir, udir, upper, RENAME_EXCHANGE);
|
||||
if (err)
|
||||
goto out_cleanup;
|
||||
|
||||
ovl_cleanup_whiteouts(upper, list);
|
||||
ovl_cleanup(wdir, upper);
|
||||
unlock_rename(workdir, upperdir);
|
||||
|
||||
/* dentry's upper doesn't match now, get rid of it */
|
||||
d_drop(dentry);
|
||||
|
||||
return opaquedir;
|
||||
|
||||
out_cleanup:
|
||||
ovl_cleanup(wdir, opaquedir);
|
||||
out_dput:
|
||||
dput(opaquedir);
|
||||
out_unlock:
|
||||
unlock_rename(workdir, upperdir);
|
||||
out:
|
||||
return ERR_PTR(err);
|
||||
}
|
||||
|
||||
static struct dentry *ovl_check_empty_and_clear(struct dentry *dentry,
|
||||
enum ovl_path_type type)
|
||||
{
|
||||
int err;
|
||||
struct dentry *ret = NULL;
|
||||
LIST_HEAD(list);
|
||||
|
||||
err = ovl_check_empty_dir(dentry, &list);
|
||||
if (err)
|
||||
ret = ERR_PTR(err);
|
||||
else if (type == OVL_PATH_MERGE)
|
||||
ret = ovl_clear_empty(dentry, &list);
|
||||
|
||||
ovl_cache_free(&list);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode,
|
||||
struct kstat *stat, const char *link,
|
||||
struct dentry *hardlink)
|
||||
{
|
||||
struct dentry *workdir = ovl_workdir(dentry);
|
||||
struct inode *wdir = workdir->d_inode;
|
||||
struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
|
||||
struct inode *udir = upperdir->d_inode;
|
||||
struct dentry *upper;
|
||||
struct dentry *newdentry;
|
||||
int err;
|
||||
|
||||
err = ovl_lock_rename_workdir(workdir, upperdir);
|
||||
if (err)
|
||||
goto out;
|
||||
|
||||
newdentry = ovl_lookup_temp(workdir, dentry);
|
||||
err = PTR_ERR(newdentry);
|
||||
if (IS_ERR(newdentry))
|
||||
goto out_unlock;
|
||||
|
||||
upper = lookup_one_len(dentry->d_name.name, upperdir,
|
||||
dentry->d_name.len);
|
||||
err = PTR_ERR(upper);
|
||||
if (IS_ERR(upper))
|
||||
goto out_dput;
|
||||
|
||||
err = ovl_create_real(wdir, newdentry, stat, link, hardlink, true);
|
||||
if (err)
|
||||
goto out_dput2;
|
||||
|
||||
if (S_ISDIR(stat->mode)) {
|
||||
err = ovl_set_opaque(newdentry);
|
||||
if (err)
|
||||
goto out_cleanup;
|
||||
|
||||
err = ovl_do_rename(wdir, newdentry, udir, upper,
|
||||
RENAME_EXCHANGE);
|
||||
if (err)
|
||||
goto out_cleanup;
|
||||
|
||||
ovl_cleanup(wdir, upper);
|
||||
} else {
|
||||
err = ovl_do_rename(wdir, newdentry, udir, upper, 0);
|
||||
if (err)
|
||||
goto out_cleanup;
|
||||
}
|
||||
ovl_dentry_version_inc(dentry->d_parent);
|
||||
ovl_dentry_update(dentry, newdentry);
|
||||
ovl_copyattr(newdentry->d_inode, inode);
|
||||
d_instantiate(dentry, inode);
|
||||
newdentry = NULL;
|
||||
out_dput2:
|
||||
dput(upper);
|
||||
out_dput:
|
||||
dput(newdentry);
|
||||
out_unlock:
|
||||
unlock_rename(workdir, upperdir);
|
||||
out:
|
||||
return err;
|
||||
|
||||
out_cleanup:
|
||||
ovl_cleanup(wdir, newdentry);
|
||||
goto out_dput2;
|
||||
}
|
||||
|
||||
static int ovl_create_or_link(struct dentry *dentry, int mode, dev_t rdev,
|
||||
const char *link, struct dentry *hardlink)
|
||||
{
|
||||
int err;
|
||||
struct inode *inode;
|
||||
struct kstat stat = {
|
||||
.mode = mode,
|
||||
.rdev = rdev,
|
||||
};
|
||||
|
||||
err = -ENOMEM;
|
||||
inode = ovl_new_inode(dentry->d_sb, mode, dentry->d_fsdata);
|
||||
if (!inode)
|
||||
goto out;
|
||||
|
||||
err = ovl_copy_up(dentry->d_parent);
|
||||
if (err)
|
||||
goto out_iput;
|
||||
|
||||
if (!ovl_dentry_is_opaque(dentry)) {
|
||||
err = ovl_create_upper(dentry, inode, &stat, link, hardlink);
|
||||
} else {
|
||||
const struct cred *old_cred;
|
||||
struct cred *override_cred;
|
||||
|
||||
err = -ENOMEM;
|
||||
override_cred = prepare_creds();
|
||||
if (!override_cred)
|
||||
goto out_iput;
|
||||
|
||||
/*
|
||||
* CAP_SYS_ADMIN for setting opaque xattr
|
||||
* CAP_DAC_OVERRIDE for create in workdir, rename
|
||||
* CAP_FOWNER for removing whiteout from sticky dir
|
||||
*/
|
||||
cap_raise(override_cred->cap_effective, CAP_SYS_ADMIN);
|
||||
cap_raise(override_cred->cap_effective, CAP_DAC_OVERRIDE);
|
||||
cap_raise(override_cred->cap_effective, CAP_FOWNER);
|
||||
old_cred = override_creds(override_cred);
|
||||
|
||||
err = ovl_create_over_whiteout(dentry, inode, &stat, link,
|
||||
hardlink);
|
||||
|
||||
revert_creds(old_cred);
|
||||
put_cred(override_cred);
|
||||
}
|
||||
|
||||
if (!err)
|
||||
inode = NULL;
|
||||
out_iput:
|
||||
iput(inode);
|
||||
out:
|
||||
return err;
|
||||
}
|
||||
|
||||
static int ovl_create_object(struct dentry *dentry, int mode, dev_t rdev,
|
||||
const char *link)
|
||||
{
|
||||
int err;
|
||||
|
||||
err = ovl_want_write(dentry);
|
||||
if (!err) {
|
||||
err = ovl_create_or_link(dentry, mode, rdev, link, NULL);
|
||||
ovl_drop_write(dentry);
|
||||
}
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
static int ovl_create(struct inode *dir, struct dentry *dentry, umode_t mode,
|
||||
bool excl)
|
||||
{
|
||||
return ovl_create_object(dentry, (mode & 07777) | S_IFREG, 0, NULL);
|
||||
}
|
||||
|
||||
static int ovl_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
|
||||
{
|
||||
return ovl_create_object(dentry, (mode & 07777) | S_IFDIR, 0, NULL);
|
||||
}
|
||||
|
||||
static int ovl_mknod(struct inode *dir, struct dentry *dentry, umode_t mode,
|
||||
dev_t rdev)
|
||||
{
|
||||
/* Don't allow creation of "whiteout" on overlay */
|
||||
if (S_ISCHR(mode) && rdev == WHITEOUT_DEV)
|
||||
return -EPERM;
|
||||
|
||||
return ovl_create_object(dentry, mode, rdev, NULL);
|
||||
}
|
||||
|
||||
static int ovl_symlink(struct inode *dir, struct dentry *dentry,
|
||||
const char *link)
|
||||
{
|
||||
return ovl_create_object(dentry, S_IFLNK, 0, link);
|
||||
}
|
||||
|
||||
static int ovl_link(struct dentry *old, struct inode *newdir,
|
||||
struct dentry *new)
|
||||
{
|
||||
int err;
|
||||
struct dentry *upper;
|
||||
|
||||
err = ovl_want_write(old);
|
||||
if (err)
|
||||
goto out;
|
||||
|
||||
err = ovl_copy_up(old);
|
||||
if (err)
|
||||
goto out_drop_write;
|
||||
|
||||
upper = ovl_dentry_upper(old);
|
||||
err = ovl_create_or_link(new, upper->d_inode->i_mode, 0, NULL, upper);
|
||||
|
||||
out_drop_write:
|
||||
ovl_drop_write(old);
|
||||
out:
|
||||
return err;
|
||||
}
|
||||
|
||||
static int ovl_remove_and_whiteout(struct dentry *dentry,
|
||||
enum ovl_path_type type, bool is_dir)
|
||||
{
|
||||
struct dentry *workdir = ovl_workdir(dentry);
|
||||
struct inode *wdir = workdir->d_inode;
|
||||
struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
|
||||
struct inode *udir = upperdir->d_inode;
|
||||
struct dentry *whiteout;
|
||||
struct dentry *upper;
|
||||
struct dentry *opaquedir = NULL;
|
||||
int err;
|
||||
|
||||
if (is_dir) {
|
||||
opaquedir = ovl_check_empty_and_clear(dentry, type);
|
||||
err = PTR_ERR(opaquedir);
|
||||
if (IS_ERR(opaquedir))
|
||||
goto out;
|
||||
}
|
||||
|
||||
err = ovl_lock_rename_workdir(workdir, upperdir);
|
||||
if (err)
|
||||
goto out_dput;
|
||||
|
||||
whiteout = ovl_whiteout(workdir, dentry);
|
||||
err = PTR_ERR(whiteout);
|
||||
if (IS_ERR(whiteout))
|
||||
goto out_unlock;
|
||||
|
||||
if (type == OVL_PATH_LOWER) {
|
||||
upper = lookup_one_len(dentry->d_name.name, upperdir,
|
||||
dentry->d_name.len);
|
||||
err = PTR_ERR(upper);
|
||||
if (IS_ERR(upper))
|
||||
goto kill_whiteout;
|
||||
|
||||
err = ovl_do_rename(wdir, whiteout, udir, upper, 0);
|
||||
dput(upper);
|
||||
if (err)
|
||||
goto kill_whiteout;
|
||||
} else {
|
||||
int flags = 0;
|
||||
|
||||
upper = ovl_dentry_upper(dentry);
|
||||
if (opaquedir)
|
||||
upper = opaquedir;
|
||||
err = -ESTALE;
|
||||
if (upper->d_parent != upperdir)
|
||||
goto kill_whiteout;
|
||||
|
||||
if (is_dir)
|
||||
flags |= RENAME_EXCHANGE;
|
||||
|
||||
err = ovl_do_rename(wdir, whiteout, udir, upper, flags);
|
||||
if (err)
|
||||
goto kill_whiteout;
|
||||
|
||||
if (is_dir)
|
||||
ovl_cleanup(wdir, upper);
|
||||
}
|
||||
ovl_dentry_version_inc(dentry->d_parent);
|
||||
out_d_drop:
|
||||
d_drop(dentry);
|
||||
dput(whiteout);
|
||||
out_unlock:
|
||||
unlock_rename(workdir, upperdir);
|
||||
out_dput:
|
||||
dput(opaquedir);
|
||||
out:
|
||||
return err;
|
||||
|
||||
kill_whiteout:
|
||||
ovl_cleanup(wdir, whiteout);
|
||||
goto out_d_drop;
|
||||
}
|
||||
|
||||
static int ovl_remove_upper(struct dentry *dentry, bool is_dir)
|
||||
{
|
||||
struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent);
|
||||
struct inode *dir = upperdir->d_inode;
|
||||
struct dentry *upper = ovl_dentry_upper(dentry);
|
||||
int err;
|
||||
|
||||
mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
|
||||
err = -ESTALE;
|
||||
if (upper->d_parent == upperdir) {
|
||||
/* Don't let d_delete() think it can reset d_inode */
|
||||
dget(upper);
|
||||
if (is_dir)
|
||||
err = vfs_rmdir(dir, upper);
|
||||
else
|
||||
err = vfs_unlink(dir, upper, NULL);
|
||||
dput(upper);
|
||||
ovl_dentry_version_inc(dentry->d_parent);
|
||||
}
|
||||
|
||||
/*
|
||||
* Keeping this dentry hashed would mean having to release
|
||||
* upperpath/lowerpath, which could only be done if we are the
|
||||
* sole user of this dentry. Too tricky... Just unhash for
|
||||
* now.
|
||||
*/
|
||||
d_drop(dentry);
|
||||
mutex_unlock(&dir->i_mutex);
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
static inline int ovl_check_sticky(struct dentry *dentry)
|
||||
{
|
||||
struct inode *dir = ovl_dentry_real(dentry->d_parent)->d_inode;
|
||||
struct inode *inode = ovl_dentry_real(dentry)->d_inode;
|
||||
|
||||
if (check_sticky(dir, inode))
|
||||
return -EPERM;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int ovl_do_remove(struct dentry *dentry, bool is_dir)
|
||||
{
|
||||
enum ovl_path_type type;
|
||||
int err;
|
||||
|
||||
err = ovl_check_sticky(dentry);
|
||||
if (err)
|
||||
goto out;
|
||||
|
||||
err = ovl_want_write(dentry);
|
||||
if (err)
|
||||
goto out;
|
||||
|
||||
err = ovl_copy_up(dentry->d_parent);
|
||||
if (err)
|
||||
goto out_drop_write;
|
||||
|
||||
type = ovl_path_type(dentry);
|
||||
if (type == OVL_PATH_PURE_UPPER) {
|
||||
err = ovl_remove_upper(dentry, is_dir);
|
||||
} else {
|
||||
const struct cred *old_cred;
|
||||
struct cred *override_cred;
|
||||
|
||||
err = -ENOMEM;
|
||||
override_cred = prepare_creds();
|
||||
if (!override_cred)
|
||||
goto out_drop_write;
|
||||
|
||||
/*
|
||||
* CAP_SYS_ADMIN for setting xattr on whiteout, opaque dir
|
||||
* CAP_DAC_OVERRIDE for create in workdir, rename
|
||||
* CAP_FOWNER for removing whiteout from sticky dir
|
||||
* CAP_FSETID for chmod of opaque dir
|
||||
* CAP_CHOWN for chown of opaque dir
|
||||
*/
|
||||
cap_raise(override_cred->cap_effective, CAP_SYS_ADMIN);
|
||||
cap_raise(override_cred->cap_effective, CAP_DAC_OVERRIDE);
|
||||
cap_raise(override_cred->cap_effective, CAP_FOWNER);
|
||||
cap_raise(override_cred->cap_effective, CAP_FSETID);
|
||||
cap_raise(override_cred->cap_effective, CAP_CHOWN);
|
||||
old_cred = override_creds(override_cred);
|
||||
|
||||
err = ovl_remove_and_whiteout(dentry, type, is_dir);
|
||||
|
||||
revert_creds(old_cred);
|
||||
put_cred(override_cred);
|
||||
}
|
||||
out_drop_write:
|
||||
ovl_drop_write(dentry);
|
||||
out:
|
||||
return err;
|
||||
}
|
||||
|
||||
static int ovl_unlink(struct inode *dir, struct dentry *dentry)
|
||||
{
|
||||
return ovl_do_remove(dentry, false);
|
||||
}
|
||||
|
||||
static int ovl_rmdir(struct inode *dir, struct dentry *dentry)
|
||||
{
|
||||
return ovl_do_remove(dentry, true);
|
||||
}
|
||||
|
||||
static int ovl_rename2(struct inode *olddir, struct dentry *old,
|
||||
struct inode *newdir, struct dentry *new,
|
||||
unsigned int flags)
|
||||
{
|
||||
int err;
|
||||
enum ovl_path_type old_type;
|
||||
enum ovl_path_type new_type;
|
||||
struct dentry *old_upperdir;
|
||||
struct dentry *new_upperdir;
|
||||
struct dentry *olddentry;
|
||||
struct dentry *newdentry;
|
||||
struct dentry *trap;
|
||||
bool old_opaque;
|
||||
bool new_opaque;
|
||||
bool new_create = false;
|
||||
bool cleanup_whiteout = false;
|
||||
bool overwrite = !(flags & RENAME_EXCHANGE);
|
||||
bool is_dir = S_ISDIR(old->d_inode->i_mode);
|
||||
bool new_is_dir = false;
|
||||
struct dentry *opaquedir = NULL;
|
||||
const struct cred *old_cred = NULL;
|
||||
struct cred *override_cred = NULL;
|
||||
|
||||
err = -EINVAL;
|
||||
if (flags & ~(RENAME_EXCHANGE | RENAME_NOREPLACE))
|
||||
goto out;
|
||||
|
||||
flags &= ~RENAME_NOREPLACE;
|
||||
|
||||
err = ovl_check_sticky(old);
|
||||
if (err)
|
||||
goto out;
|
||||
|
||||
/* Don't copy up directory trees */
|
||||
old_type = ovl_path_type(old);
|
||||
err = -EXDEV;
|
||||
if ((old_type == OVL_PATH_LOWER || old_type == OVL_PATH_MERGE) && is_dir)
|
||||
goto out;
|
||||
|
||||
if (new->d_inode) {
|
||||
err = ovl_check_sticky(new);
|
||||
if (err)
|
||||
goto out;
|
||||
|
||||
if (S_ISDIR(new->d_inode->i_mode))
|
||||
new_is_dir = true;
|
||||
|
||||
new_type = ovl_path_type(new);
|
||||
err = -EXDEV;
|
||||
if (!overwrite && (new_type == OVL_PATH_LOWER || new_type == OVL_PATH_MERGE) && new_is_dir)
|
||||
goto out;
|
||||
|
||||
err = 0;
|
||||
if (new_type == OVL_PATH_LOWER && old_type == OVL_PATH_LOWER) {
|
||||
if (ovl_dentry_lower(old)->d_inode ==
|
||||
ovl_dentry_lower(new)->d_inode)
|
||||
goto out;
|
||||
}
|
||||
if (new_type != OVL_PATH_LOWER && old_type != OVL_PATH_LOWER) {
|
||||
if (ovl_dentry_upper(old)->d_inode ==
|
||||
ovl_dentry_upper(new)->d_inode)
|
||||
goto out;
|
||||
}
|
||||
} else {
|
||||
if (ovl_dentry_is_opaque(new))
|
||||
new_type = OVL_PATH_UPPER;
|
||||
else
|
||||
new_type = OVL_PATH_PURE_UPPER;
|
||||
}
|
||||
|
||||
err = ovl_want_write(old);
|
||||
if (err)
|
||||
goto out;
|
||||
|
||||
err = ovl_copy_up(old);
|
||||
if (err)
|
||||
goto out_drop_write;
|
||||
|
||||
err = ovl_copy_up(new->d_parent);
|
||||
if (err)
|
||||
goto out_drop_write;
|
||||
if (!overwrite) {
|
||||
err = ovl_copy_up(new);
|
||||
if (err)
|
||||
goto out_drop_write;
|
||||
}
|
||||
|
||||
old_opaque = old_type != OVL_PATH_PURE_UPPER;
|
||||
new_opaque = new_type != OVL_PATH_PURE_UPPER;
|
||||
|
||||
if (old_opaque || new_opaque) {
|
||||
err = -ENOMEM;
|
||||
override_cred = prepare_creds();
|
||||
if (!override_cred)
|
||||
goto out_drop_write;
|
||||
|
||||
/*
|
||||
* CAP_SYS_ADMIN for setting xattr on whiteout, opaque dir
|
||||
* CAP_DAC_OVERRIDE for create in workdir
|
||||
* CAP_FOWNER for removing whiteout from sticky dir
|
||||
* CAP_FSETID for chmod of opaque dir
|
||||
* CAP_CHOWN for chown of opaque dir
|
||||
*/
|
||||
cap_raise(override_cred->cap_effective, CAP_SYS_ADMIN);
|
||||
cap_raise(override_cred->cap_effective, CAP_DAC_OVERRIDE);
|
||||
cap_raise(override_cred->cap_effective, CAP_FOWNER);
|
||||
cap_raise(override_cred->cap_effective, CAP_FSETID);
|
||||
cap_raise(override_cred->cap_effective, CAP_CHOWN);
|
||||
old_cred = override_creds(override_cred);
|
||||
}
|
||||
|
||||
if (overwrite && (new_type == OVL_PATH_LOWER || new_type == OVL_PATH_MERGE) && new_is_dir) {
|
||||
opaquedir = ovl_check_empty_and_clear(new, new_type);
|
||||
err = PTR_ERR(opaquedir);
|
||||
if (IS_ERR(opaquedir)) {
|
||||
opaquedir = NULL;
|
||||
goto out_revert_creds;
|
||||
}
|
||||
}
|
||||
|
||||
if (overwrite) {
|
||||
if (old_opaque) {
|
||||
if (new->d_inode || !new_opaque) {
|
||||
/* Whiteout source */
|
||||
flags |= RENAME_WHITEOUT;
|
||||
} else {
|
||||
/* Switch whiteouts */
|
||||
flags |= RENAME_EXCHANGE;
|
||||
}
|
||||
} else if (is_dir && !new->d_inode && new_opaque) {
|
||||
flags |= RENAME_EXCHANGE;
|
||||
cleanup_whiteout = true;
|
||||
}
|
||||
}
|
||||
|
||||
old_upperdir = ovl_dentry_upper(old->d_parent);
|
||||
new_upperdir = ovl_dentry_upper(new->d_parent);
|
||||
|
||||
trap = lock_rename(new_upperdir, old_upperdir);
|
||||
|
||||
olddentry = ovl_dentry_upper(old);
|
||||
newdentry = ovl_dentry_upper(new);
|
||||
if (newdentry) {
|
||||
if (opaquedir) {
|
||||
newdentry = opaquedir;
|
||||
opaquedir = NULL;
|
||||
} else {
|
||||
dget(newdentry);
|
||||
}
|
||||
} else {
|
||||
new_create = true;
|
||||
newdentry = lookup_one_len(new->d_name.name, new_upperdir,
|
||||
new->d_name.len);
|
||||
err = PTR_ERR(newdentry);
|
||||
if (IS_ERR(newdentry))
|
||||
goto out_unlock;
|
||||
}
|
||||
|
||||
err = -ESTALE;
|
||||
if (olddentry->d_parent != old_upperdir)
|
||||
goto out_dput;
|
||||
if (newdentry->d_parent != new_upperdir)
|
||||
goto out_dput;
|
||||
if (olddentry == trap)
|
||||
goto out_dput;
|
||||
if (newdentry == trap)
|
||||
goto out_dput;
|
||||
|
||||
if (is_dir && !old_opaque && new_opaque) {
|
||||
err = ovl_set_opaque(olddentry);
|
||||
if (err)
|
||||
goto out_dput;
|
||||
}
|
||||
if (!overwrite && new_is_dir && old_opaque && !new_opaque) {
|
||||
err = ovl_set_opaque(newdentry);
|
||||
if (err)
|
||||
goto out_dput;
|
||||
}
|
||||
|
||||
if (old_opaque || new_opaque) {
|
||||
err = ovl_do_rename(old_upperdir->d_inode, olddentry,
|
||||
new_upperdir->d_inode, newdentry,
|
||||
flags);
|
||||
} else {
|
||||
/* No debug for the plain case */
|
||||
BUG_ON(flags & ~RENAME_EXCHANGE);
|
||||
err = vfs_rename(old_upperdir->d_inode, olddentry,
|
||||
new_upperdir->d_inode, newdentry,
|
||||
NULL, flags);
|
||||
}
|
||||
|
||||
if (err) {
|
||||
if (is_dir && !old_opaque && new_opaque)
|
||||
ovl_remove_opaque(olddentry);
|
||||
if (!overwrite && new_is_dir && old_opaque && !new_opaque)
|
||||
ovl_remove_opaque(newdentry);
|
||||
goto out_dput;
|
||||
}
|
||||
|
||||
if (is_dir && old_opaque && !new_opaque)
|
||||
ovl_remove_opaque(olddentry);
|
||||
if (!overwrite && new_is_dir && !old_opaque && new_opaque)
|
||||
ovl_remove_opaque(newdentry);
|
||||
|
||||
if (old_opaque != new_opaque) {
|
||||
ovl_dentry_set_opaque(old, new_opaque);
|
||||
if (!overwrite)
|
||||
ovl_dentry_set_opaque(new, old_opaque);
|
||||
}
|
||||
|
||||
if (cleanup_whiteout)
|
||||
ovl_cleanup(old_upperdir->d_inode, newdentry);
|
||||
|
||||
ovl_dentry_version_inc(old->d_parent);
|
||||
ovl_dentry_version_inc(new->d_parent);
|
||||
|
||||
out_dput:
|
||||
dput(newdentry);
|
||||
out_unlock:
|
||||
unlock_rename(new_upperdir, old_upperdir);
|
||||
out_revert_creds:
|
||||
if (old_opaque || new_opaque) {
|
||||
revert_creds(old_cred);
|
||||
put_cred(override_cred);
|
||||
}
|
||||
out_drop_write:
|
||||
ovl_drop_write(old);
|
||||
out:
|
||||
dput(opaquedir);
|
||||
return err;
|
||||
}
|
||||
|
||||
const struct inode_operations ovl_dir_inode_operations = {
|
||||
.lookup = ovl_lookup,
|
||||
.mkdir = ovl_mkdir,
|
||||
.symlink = ovl_symlink,
|
||||
.unlink = ovl_unlink,
|
||||
.rmdir = ovl_rmdir,
|
||||
.rename2 = ovl_rename2,
|
||||
.link = ovl_link,
|
||||
.setattr = ovl_setattr,
|
||||
.create = ovl_create,
|
||||
.mknod = ovl_mknod,
|
||||
.permission = ovl_permission,
|
||||
.getattr = ovl_dir_getattr,
|
||||
.setxattr = ovl_setxattr,
|
||||
.getxattr = ovl_getxattr,
|
||||
.listxattr = ovl_listxattr,
|
||||
.removexattr = ovl_removexattr,
|
||||
};
|
||||
|
|
@ -0,0 +1,425 @@
|
|||
/*
|
||||
*
|
||||
* Copyright (C) 2011 Novell Inc.
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify it
|
||||
* under the terms of the GNU General Public License version 2 as published by
|
||||
* the Free Software Foundation.
|
||||
*/
|
||||
|
||||
#include <linux/fs.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/xattr.h>
|
||||
#include "overlayfs.h"
|
||||
|
||||
static int ovl_copy_up_last(struct dentry *dentry, struct iattr *attr,
|
||||
bool no_data)
|
||||
{
|
||||
int err;
|
||||
struct dentry *parent;
|
||||
struct kstat stat;
|
||||
struct path lowerpath;
|
||||
|
||||
parent = dget_parent(dentry);
|
||||
err = ovl_copy_up(parent);
|
||||
if (err)
|
||||
goto out_dput_parent;
|
||||
|
||||
ovl_path_lower(dentry, &lowerpath);
|
||||
err = vfs_getattr(&lowerpath, &stat);
|
||||
if (err)
|
||||
goto out_dput_parent;
|
||||
|
||||
if (no_data)
|
||||
stat.size = 0;
|
||||
|
||||
err = ovl_copy_up_one(parent, dentry, &lowerpath, &stat, attr);
|
||||
|
||||
out_dput_parent:
|
||||
dput(parent);
|
||||
return err;
|
||||
}
|
||||
|
||||
int ovl_setattr(struct dentry *dentry, struct iattr *attr)
|
||||
{
|
||||
int err;
|
||||
struct dentry *upperdentry;
|
||||
|
||||
err = ovl_want_write(dentry);
|
||||
if (err)
|
||||
goto out;
|
||||
|
||||
upperdentry = ovl_dentry_upper(dentry);
|
||||
if (upperdentry) {
|
||||
mutex_lock(&upperdentry->d_inode->i_mutex);
|
||||
err = notify_change(upperdentry, attr, NULL);
|
||||
mutex_unlock(&upperdentry->d_inode->i_mutex);
|
||||
} else {
|
||||
err = ovl_copy_up_last(dentry, attr, false);
|
||||
}
|
||||
ovl_drop_write(dentry);
|
||||
out:
|
||||
return err;
|
||||
}
|
||||
|
||||
static int ovl_getattr(struct vfsmount *mnt, struct dentry *dentry,
|
||||
struct kstat *stat)
|
||||
{
|
||||
struct path realpath;
|
||||
|
||||
ovl_path_real(dentry, &realpath);
|
||||
return vfs_getattr(&realpath, stat);
|
||||
}
|
||||
|
||||
int ovl_permission(struct inode *inode, int mask)
|
||||
{
|
||||
struct ovl_entry *oe;
|
||||
struct dentry *alias = NULL;
|
||||
struct inode *realinode;
|
||||
struct dentry *realdentry;
|
||||
bool is_upper;
|
||||
int err;
|
||||
|
||||
if (S_ISDIR(inode->i_mode)) {
|
||||
oe = inode->i_private;
|
||||
} else if (mask & MAY_NOT_BLOCK) {
|
||||
return -ECHILD;
|
||||
} else {
|
||||
/*
|
||||
* For non-directories find an alias and get the info
|
||||
* from there.
|
||||
*/
|
||||
alias = d_find_any_alias(inode);
|
||||
if (WARN_ON(!alias))
|
||||
return -ENOENT;
|
||||
|
||||
oe = alias->d_fsdata;
|
||||
}
|
||||
|
||||
realdentry = ovl_entry_real(oe, &is_upper);
|
||||
|
||||
/* Careful in RCU walk mode */
|
||||
realinode = ACCESS_ONCE(realdentry->d_inode);
|
||||
if (!realinode) {
|
||||
WARN_ON(!(mask & MAY_NOT_BLOCK));
|
||||
err = -ENOENT;
|
||||
goto out_dput;
|
||||
}
|
||||
|
||||
if (mask & MAY_WRITE) {
|
||||
umode_t mode = realinode->i_mode;
|
||||
|
||||
/*
|
||||
* Writes will always be redirected to upper layer, so
|
||||
* ignore lower layer being read-only.
|
||||
*
|
||||
* If the overlay itself is read-only then proceed
|
||||
* with the permission check, don't return EROFS.
|
||||
* This will only happen if this is the lower layer of
|
||||
* another overlayfs.
|
||||
*
|
||||
* If upper fs becomes read-only after the overlay was
|
||||
* constructed return EROFS to prevent modification of
|
||||
* upper layer.
|
||||
*/
|
||||
err = -EROFS;
|
||||
if (is_upper && !IS_RDONLY(inode) && IS_RDONLY(realinode) &&
|
||||
(S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
|
||||
goto out_dput;
|
||||
}
|
||||
|
||||
err = __inode_permission(realinode, mask);
|
||||
out_dput:
|
||||
dput(alias);
|
||||
return err;
|
||||
}
|
||||
|
||||
|
||||
struct ovl_link_data {
|
||||
struct dentry *realdentry;
|
||||
void *cookie;
|
||||
};
|
||||
|
||||
static void *ovl_follow_link(struct dentry *dentry, struct nameidata *nd)
|
||||
{
|
||||
void *ret;
|
||||
struct dentry *realdentry;
|
||||
struct inode *realinode;
|
||||
|
||||
realdentry = ovl_dentry_real(dentry);
|
||||
realinode = realdentry->d_inode;
|
||||
|
||||
if (WARN_ON(!realinode->i_op->follow_link))
|
||||
return ERR_PTR(-EPERM);
|
||||
|
||||
ret = realinode->i_op->follow_link(realdentry, nd);
|
||||
if (IS_ERR(ret))
|
||||
return ret;
|
||||
|
||||
if (realinode->i_op->put_link) {
|
||||
struct ovl_link_data *data;
|
||||
|
||||
data = kmalloc(sizeof(struct ovl_link_data), GFP_KERNEL);
|
||||
if (!data) {
|
||||
realinode->i_op->put_link(realdentry, nd, ret);
|
||||
return ERR_PTR(-ENOMEM);
|
||||
}
|
||||
data->realdentry = realdentry;
|
||||
data->cookie = ret;
|
||||
|
||||
return data;
|
||||
} else {
|
||||
return NULL;
|
||||
}
|
||||
}
|
||||
|
||||
static void ovl_put_link(struct dentry *dentry, struct nameidata *nd, void *c)
|
||||
{
|
||||
struct inode *realinode;
|
||||
struct ovl_link_data *data = c;
|
||||
|
||||
if (!data)
|
||||
return;
|
||||
|
||||
realinode = data->realdentry->d_inode;
|
||||
realinode->i_op->put_link(data->realdentry, nd, data->cookie);
|
||||
kfree(data);
|
||||
}
|
||||
|
||||
static int ovl_readlink(struct dentry *dentry, char __user *buf, int bufsiz)
|
||||
{
|
||||
struct path realpath;
|
||||
struct inode *realinode;
|
||||
|
||||
ovl_path_real(dentry, &realpath);
|
||||
realinode = realpath.dentry->d_inode;
|
||||
|
||||
if (!realinode->i_op->readlink)
|
||||
return -EINVAL;
|
||||
|
||||
touch_atime(&realpath);
|
||||
|
||||
return realinode->i_op->readlink(realpath.dentry, buf, bufsiz);
|
||||
}
|
||||
|
||||
|
||||
static bool ovl_is_private_xattr(const char *name)
|
||||
{
|
||||
return strncmp(name, "trusted.overlay.", 14) == 0;
|
||||
}
|
||||
|
||||
int ovl_setxattr(struct dentry *dentry, const char *name,
|
||||
const void *value, size_t size, int flags)
|
||||
{
|
||||
int err;
|
||||
struct dentry *upperdentry;
|
||||
|
||||
err = ovl_want_write(dentry);
|
||||
if (err)
|
||||
goto out;
|
||||
|
||||
err = -EPERM;
|
||||
if (ovl_is_private_xattr(name))
|
||||
goto out_drop_write;
|
||||
|
||||
err = ovl_copy_up(dentry);
|
||||
if (err)
|
||||
goto out_drop_write;
|
||||
|
||||
upperdentry = ovl_dentry_upper(dentry);
|
||||
err = vfs_setxattr(upperdentry, name, value, size, flags);
|
||||
|
||||
out_drop_write:
|
||||
ovl_drop_write(dentry);
|
||||
out:
|
||||
return err;
|
||||
}
|
||||
|
||||
ssize_t ovl_getxattr(struct dentry *dentry, const char *name,
|
||||
void *value, size_t size)
|
||||
{
|
||||
if (ovl_path_type(dentry->d_parent) == OVL_PATH_MERGE &&
|
||||
ovl_is_private_xattr(name))
|
||||
return -ENODATA;
|
||||
|
||||
return vfs_getxattr(ovl_dentry_real(dentry), name, value, size);
|
||||
}
|
||||
|
||||
ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size)
|
||||
{
|
||||
ssize_t res;
|
||||
int off;
|
||||
|
||||
res = vfs_listxattr(ovl_dentry_real(dentry), list, size);
|
||||
if (res <= 0 || size == 0)
|
||||
return res;
|
||||
|
||||
if (ovl_path_type(dentry->d_parent) != OVL_PATH_MERGE)
|
||||
return res;
|
||||
|
||||
/* filter out private xattrs */
|
||||
for (off = 0; off < res;) {
|
||||
char *s = list + off;
|
||||
size_t slen = strlen(s) + 1;
|
||||
|
||||
BUG_ON(off + slen > res);
|
||||
|
||||
if (ovl_is_private_xattr(s)) {
|
||||
res -= slen;
|
||||
memmove(s, s + slen, res - off);
|
||||
} else {
|
||||
off += slen;
|
||||
}
|
||||
}
|
||||
|
||||
return res;
|
||||
}
|
||||
|
||||
int ovl_removexattr(struct dentry *dentry, const char *name)
|
||||
{
|
||||
int err;
|
||||
struct path realpath;
|
||||
enum ovl_path_type type;
|
||||
|
||||
err = ovl_want_write(dentry);
|
||||
if (err)
|
||||
goto out;
|
||||
|
||||
if (ovl_path_type(dentry->d_parent) == OVL_PATH_MERGE &&
|
||||
ovl_is_private_xattr(name))
|
||||
goto out_drop_write;
|
||||
|
||||
type = ovl_path_real(dentry, &realpath);
|
||||
if (type == OVL_PATH_LOWER) {
|
||||
err = vfs_getxattr(realpath.dentry, name, NULL, 0);
|
||||
if (err < 0)
|
||||
goto out_drop_write;
|
||||
|
||||
err = ovl_copy_up(dentry);
|
||||
if (err)
|
||||
goto out_drop_write;
|
||||
|
||||
ovl_path_upper(dentry, &realpath);
|
||||
}
|
||||
|
||||
err = vfs_removexattr(realpath.dentry, name);
|
||||
out_drop_write:
|
||||
ovl_drop_write(dentry);
|
||||
out:
|
||||
return err;
|
||||
}
|
||||
|
||||
static bool ovl_open_need_copy_up(int flags, enum ovl_path_type type,
|
||||
struct dentry *realdentry)
|
||||
{
|
||||
if (type != OVL_PATH_LOWER)
|
||||
return false;
|
||||
|
||||
if (special_file(realdentry->d_inode->i_mode))
|
||||
return false;
|
||||
|
||||
if (!(OPEN_FMODE(flags) & FMODE_WRITE) && !(flags & O_TRUNC))
|
||||
return false;
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
static int ovl_dentry_open(struct dentry *dentry, struct file *file,
|
||||
const struct cred *cred)
|
||||
{
|
||||
int err;
|
||||
struct path realpath;
|
||||
enum ovl_path_type type;
|
||||
bool want_write = false;
|
||||
|
||||
type = ovl_path_real(dentry, &realpath);
|
||||
if (ovl_open_need_copy_up(file->f_flags, type, realpath.dentry)) {
|
||||
want_write = true;
|
||||
err = ovl_want_write(dentry);
|
||||
if (err)
|
||||
goto out;
|
||||
|
||||
if (file->f_flags & O_TRUNC)
|
||||
err = ovl_copy_up_last(dentry, NULL, true);
|
||||
else
|
||||
err = ovl_copy_up(dentry);
|
||||
if (err)
|
||||
goto out_drop_write;
|
||||
|
||||
ovl_path_upper(dentry, &realpath);
|
||||
}
|
||||
|
||||
err = vfs_open(&realpath, file, cred);
|
||||
out_drop_write:
|
||||
if (want_write)
|
||||
ovl_drop_write(dentry);
|
||||
out:
|
||||
return err;
|
||||
}
|
||||
|
||||
static const struct inode_operations ovl_file_inode_operations = {
|
||||
.setattr = ovl_setattr,
|
||||
.permission = ovl_permission,
|
||||
.getattr = ovl_getattr,
|
||||
.setxattr = ovl_setxattr,
|
||||
.getxattr = ovl_getxattr,
|
||||
.listxattr = ovl_listxattr,
|
||||
.removexattr = ovl_removexattr,
|
||||
.dentry_open = ovl_dentry_open,
|
||||
};
|
||||
|
||||
static const struct inode_operations ovl_symlink_inode_operations = {
|
||||
.setattr = ovl_setattr,
|
||||
.follow_link = ovl_follow_link,
|
||||
.put_link = ovl_put_link,
|
||||
.readlink = ovl_readlink,
|
||||
.getattr = ovl_getattr,
|
||||
.setxattr = ovl_setxattr,
|
||||
.getxattr = ovl_getxattr,
|
||||
.listxattr = ovl_listxattr,
|
||||
.removexattr = ovl_removexattr,
|
||||
};
|
||||
|
||||
struct inode *ovl_new_inode(struct super_block *sb, umode_t mode,
|
||||
struct ovl_entry *oe)
|
||||
{
|
||||
struct inode *inode;
|
||||
|
||||
inode = new_inode(sb);
|
||||
if (!inode)
|
||||
return NULL;
|
||||
|
||||
mode &= S_IFMT;
|
||||
|
||||
inode->i_ino = get_next_ino();
|
||||
inode->i_mode = mode;
|
||||
inode->i_flags |= S_NOATIME | S_NOCMTIME;
|
||||
|
||||
switch (mode) {
|
||||
case S_IFDIR:
|
||||
inode->i_private = oe;
|
||||
inode->i_op = &ovl_dir_inode_operations;
|
||||
inode->i_fop = &ovl_dir_operations;
|
||||
break;
|
||||
|
||||
case S_IFLNK:
|
||||
inode->i_op = &ovl_symlink_inode_operations;
|
||||
break;
|
||||
|
||||
case S_IFREG:
|
||||
case S_IFSOCK:
|
||||
case S_IFBLK:
|
||||
case S_IFCHR:
|
||||
case S_IFIFO:
|
||||
inode->i_op = &ovl_file_inode_operations;
|
||||
break;
|
||||
|
||||
default:
|
||||
WARN(1, "illegal file type: %i\n", mode);
|
||||
iput(inode);
|
||||
inode = NULL;
|
||||
}
|
||||
|
||||
return inode;
|
||||
|
||||
}
|
||||
|
|
@ -0,0 +1,191 @@
|
|||
/*
|
||||
*
|
||||
* Copyright (C) 2011 Novell Inc.
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify it
|
||||
* under the terms of the GNU General Public License version 2 as published by
|
||||
* the Free Software Foundation.
|
||||
*/
|
||||
|
||||
#include <linux/kernel.h>
|
||||
|
||||
struct ovl_entry;
|
||||
|
||||
enum ovl_path_type {
|
||||
OVL_PATH_PURE_UPPER,
|
||||
OVL_PATH_UPPER,
|
||||
OVL_PATH_MERGE,
|
||||
OVL_PATH_LOWER,
|
||||
};
|
||||
|
||||
extern const char *ovl_opaque_xattr;
|
||||
|
||||
static inline int ovl_do_rmdir(struct inode *dir, struct dentry *dentry)
|
||||
{
|
||||
int err = vfs_rmdir(dir, dentry);
|
||||
pr_debug("rmdir(%pd2) = %i\n", dentry, err);
|
||||
return err;
|
||||
}
|
||||
|
||||
static inline int ovl_do_unlink(struct inode *dir, struct dentry *dentry)
|
||||
{
|
||||
int err = vfs_unlink(dir, dentry, NULL);
|
||||
pr_debug("unlink(%pd2) = %i\n", dentry, err);
|
||||
return err;
|
||||
}
|
||||
|
||||
static inline int ovl_do_link(struct dentry *old_dentry, struct inode *dir,
|
||||
struct dentry *new_dentry, bool debug)
|
||||
{
|
||||
int err = vfs_link(old_dentry, dir, new_dentry, NULL);
|
||||
if (debug) {
|
||||
pr_debug("link(%pd2, %pd2) = %i\n",
|
||||
old_dentry, new_dentry, err);
|
||||
}
|
||||
return err;
|
||||
}
|
||||
|
||||
static inline int ovl_do_create(struct inode *dir, struct dentry *dentry,
|
||||
umode_t mode, bool debug)
|
||||
{
|
||||
int err = vfs_create(dir, dentry, mode, true);
|
||||
if (debug)
|
||||
pr_debug("create(%pd2, 0%o) = %i\n", dentry, mode, err);
|
||||
return err;
|
||||
}
|
||||
|
||||
static inline int ovl_do_mkdir(struct inode *dir, struct dentry *dentry,
|
||||
umode_t mode, bool debug)
|
||||
{
|
||||
int err = vfs_mkdir(dir, dentry, mode);
|
||||
if (debug)
|
||||
pr_debug("mkdir(%pd2, 0%o) = %i\n", dentry, mode, err);
|
||||
return err;
|
||||
}
|
||||
|
||||
static inline int ovl_do_mknod(struct inode *dir, struct dentry *dentry,
|
||||
umode_t mode, dev_t dev, bool debug)
|
||||
{
|
||||
int err = vfs_mknod(dir, dentry, mode, dev);
|
||||
if (debug) {
|
||||
pr_debug("mknod(%pd2, 0%o, 0%o) = %i\n",
|
||||
dentry, mode, dev, err);
|
||||
}
|
||||
return err;
|
||||
}
|
||||
|
||||
static inline int ovl_do_symlink(struct inode *dir, struct dentry *dentry,
|
||||
const char *oldname, bool debug)
|
||||
{
|
||||
int err = vfs_symlink(dir, dentry, oldname);
|
||||
if (debug)
|
||||
pr_debug("symlink(\"%s\", %pd2) = %i\n", oldname, dentry, err);
|
||||
return err;
|
||||
}
|
||||
|
||||
static inline int ovl_do_setxattr(struct dentry *dentry, const char *name,
|
||||
const void *value, size_t size, int flags)
|
||||
{
|
||||
int err = vfs_setxattr(dentry, name, value, size, flags);
|
||||
pr_debug("setxattr(%pd2, \"%s\", \"%*s\", 0x%x) = %i\n",
|
||||
dentry, name, (int) size, (char *) value, flags, err);
|
||||
return err;
|
||||
}
|
||||
|
||||
static inline int ovl_do_removexattr(struct dentry *dentry, const char *name)
|
||||
{
|
||||
int err = vfs_removexattr(dentry, name);
|
||||
pr_debug("removexattr(%pd2, \"%s\") = %i\n", dentry, name, err);
|
||||
return err;
|
||||
}
|
||||
|
||||
static inline int ovl_do_rename(struct inode *olddir, struct dentry *olddentry,
|
||||
struct inode *newdir, struct dentry *newdentry,
|
||||
unsigned int flags)
|
||||
{
|
||||
int err;
|
||||
|
||||
pr_debug("rename2(%pd2, %pd2, 0x%x)\n",
|
||||
olddentry, newdentry, flags);
|
||||
|
||||
err = vfs_rename(olddir, olddentry, newdir, newdentry, NULL, flags);
|
||||
|
||||
if (err) {
|
||||
pr_debug("...rename2(%pd2, %pd2, ...) = %i\n",
|
||||
olddentry, newdentry, err);
|
||||
}
|
||||
return err;
|
||||
}
|
||||
|
||||
static inline int ovl_do_whiteout(struct inode *dir, struct dentry *dentry)
|
||||
{
|
||||
int err = vfs_whiteout(dir, dentry);
|
||||
pr_debug("whiteout(%pd2) = %i\n", dentry, err);
|
||||
return err;
|
||||
}
|
||||
|
||||
enum ovl_path_type ovl_path_type(struct dentry *dentry);
|
||||
u64 ovl_dentry_version_get(struct dentry *dentry);
|
||||
void ovl_dentry_version_inc(struct dentry *dentry);
|
||||
void ovl_path_upper(struct dentry *dentry, struct path *path);
|
||||
void ovl_path_lower(struct dentry *dentry, struct path *path);
|
||||
enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path);
|
||||
struct dentry *ovl_dentry_upper(struct dentry *dentry);
|
||||
struct dentry *ovl_dentry_lower(struct dentry *dentry);
|
||||
struct dentry *ovl_dentry_real(struct dentry *dentry);
|
||||
struct dentry *ovl_entry_real(struct ovl_entry *oe, bool *is_upper);
|
||||
struct ovl_dir_cache *ovl_dir_cache(struct dentry *dentry);
|
||||
void ovl_set_dir_cache(struct dentry *dentry, struct ovl_dir_cache *cache);
|
||||
struct dentry *ovl_workdir(struct dentry *dentry);
|
||||
int ovl_want_write(struct dentry *dentry);
|
||||
void ovl_drop_write(struct dentry *dentry);
|
||||
bool ovl_dentry_is_opaque(struct dentry *dentry);
|
||||
void ovl_dentry_set_opaque(struct dentry *dentry, bool opaque);
|
||||
bool ovl_is_whiteout(struct dentry *dentry);
|
||||
void ovl_dentry_update(struct dentry *dentry, struct dentry *upperdentry);
|
||||
struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
|
||||
unsigned int flags);
|
||||
struct file *ovl_path_open(struct path *path, int flags);
|
||||
|
||||
struct dentry *ovl_upper_create(struct dentry *upperdir, struct dentry *dentry,
|
||||
struct kstat *stat, const char *link);
|
||||
|
||||
/* readdir.c */
|
||||
extern const struct file_operations ovl_dir_operations;
|
||||
int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list);
|
||||
void ovl_cleanup_whiteouts(struct dentry *upper, struct list_head *list);
|
||||
void ovl_cache_free(struct list_head *list);
|
||||
|
||||
/* inode.c */
|
||||
int ovl_setattr(struct dentry *dentry, struct iattr *attr);
|
||||
int ovl_permission(struct inode *inode, int mask);
|
||||
int ovl_setxattr(struct dentry *dentry, const char *name,
|
||||
const void *value, size_t size, int flags);
|
||||
ssize_t ovl_getxattr(struct dentry *dentry, const char *name,
|
||||
void *value, size_t size);
|
||||
ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size);
|
||||
int ovl_removexattr(struct dentry *dentry, const char *name);
|
||||
|
||||
struct inode *ovl_new_inode(struct super_block *sb, umode_t mode,
|
||||
struct ovl_entry *oe);
|
||||
static inline void ovl_copyattr(struct inode *from, struct inode *to)
|
||||
{
|
||||
to->i_uid = from->i_uid;
|
||||
to->i_gid = from->i_gid;
|
||||
}
|
||||
|
||||
/* dir.c */
|
||||
extern const struct inode_operations ovl_dir_inode_operations;
|
||||
struct dentry *ovl_lookup_temp(struct dentry *workdir, struct dentry *dentry);
|
||||
int ovl_create_real(struct inode *dir, struct dentry *newdentry,
|
||||
struct kstat *stat, const char *link,
|
||||
struct dentry *hardlink, bool debug);
|
||||
void ovl_cleanup(struct inode *dir, struct dentry *dentry);
|
||||
|
||||
/* copy_up.c */
|
||||
int ovl_copy_up(struct dentry *dentry);
|
||||
int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry,
|
||||
struct path *lowerpath, struct kstat *stat,
|
||||
struct iattr *attr);
|
||||
int ovl_copy_xattr(struct dentry *old, struct dentry *new);
|
||||
int ovl_set_attr(struct dentry *upper, struct kstat *stat);
|
||||
|
|
@ -0,0 +1,587 @@
|
|||
/*
|
||||
*
|
||||
* Copyright (C) 2011 Novell Inc.
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify it
|
||||
* under the terms of the GNU General Public License version 2 as published by
|
||||
* the Free Software Foundation.
|
||||
*/
|
||||
|
||||
#include <linux/fs.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/namei.h>
|
||||
#include <linux/file.h>
|
||||
#include <linux/xattr.h>
|
||||
#include <linux/rbtree.h>
|
||||
#include <linux/security.h>
|
||||
#include <linux/cred.h>
|
||||
#include "overlayfs.h"
|
||||
|
||||
struct ovl_cache_entry {
|
||||
const char *name;
|
||||
unsigned int len;
|
||||
unsigned int type;
|
||||
u64 ino;
|
||||
bool is_whiteout;
|
||||
struct list_head l_node;
|
||||
struct rb_node node;
|
||||
};
|
||||
|
||||
struct ovl_dir_cache {
|
||||
long refcount;
|
||||
u64 version;
|
||||
struct list_head entries;
|
||||
};
|
||||
|
||||
struct ovl_readdir_data {
|
||||
struct dir_context ctx;
|
||||
bool is_merge;
|
||||
struct rb_root *root;
|
||||
struct list_head *list;
|
||||
struct list_head *middle;
|
||||
int count;
|
||||
int err;
|
||||
};
|
||||
|
||||
struct ovl_dir_file {
|
||||
bool is_real;
|
||||
bool is_upper;
|
||||
struct ovl_dir_cache *cache;
|
||||
struct ovl_cache_entry cursor;
|
||||
struct file *realfile;
|
||||
struct file *upperfile;
|
||||
};
|
||||
|
||||
static struct ovl_cache_entry *ovl_cache_entry_from_node(struct rb_node *n)
|
||||
{
|
||||
return container_of(n, struct ovl_cache_entry, node);
|
||||
}
|
||||
|
||||
static struct ovl_cache_entry *ovl_cache_entry_find(struct rb_root *root,
|
||||
const char *name, int len)
|
||||
{
|
||||
struct rb_node *node = root->rb_node;
|
||||
int cmp;
|
||||
|
||||
while (node) {
|
||||
struct ovl_cache_entry *p = ovl_cache_entry_from_node(node);
|
||||
|
||||
cmp = strncmp(name, p->name, len);
|
||||
if (cmp > 0)
|
||||
node = p->node.rb_right;
|
||||
else if (cmp < 0 || len < p->len)
|
||||
node = p->node.rb_left;
|
||||
else
|
||||
return p;
|
||||
}
|
||||
|
||||
return NULL;
|
||||
}
|
||||
|
||||
static struct ovl_cache_entry *ovl_cache_entry_new(const char *name, int len,
|
||||
u64 ino, unsigned int d_type)
|
||||
{
|
||||
struct ovl_cache_entry *p;
|
||||
|
||||
p = kmalloc(sizeof(*p) + len + 1, GFP_KERNEL);
|
||||
if (p) {
|
||||
char *name_copy = (char *) (p + 1);
|
||||
memcpy(name_copy, name, len);
|
||||
name_copy[len] = '\0';
|
||||
p->name = name_copy;
|
||||
p->len = len;
|
||||
p->type = d_type;
|
||||
p->ino = ino;
|
||||
p->is_whiteout = false;
|
||||
}
|
||||
|
||||
return p;
|
||||
}
|
||||
|
||||
static int ovl_cache_entry_add_rb(struct ovl_readdir_data *rdd,
|
||||
const char *name, int len, u64 ino,
|
||||
unsigned int d_type)
|
||||
{
|
||||
struct rb_node **newp = &rdd->root->rb_node;
|
||||
struct rb_node *parent = NULL;
|
||||
struct ovl_cache_entry *p;
|
||||
|
||||
while (*newp) {
|
||||
int cmp;
|
||||
struct ovl_cache_entry *tmp;
|
||||
|
||||
parent = *newp;
|
||||
tmp = ovl_cache_entry_from_node(*newp);
|
||||
cmp = strncmp(name, tmp->name, len);
|
||||
if (cmp > 0)
|
||||
newp = &tmp->node.rb_right;
|
||||
else if (cmp < 0 || len < tmp->len)
|
||||
newp = &tmp->node.rb_left;
|
||||
else
|
||||
return 0;
|
||||
}
|
||||
|
||||
p = ovl_cache_entry_new(name, len, ino, d_type);
|
||||
if (p == NULL)
|
||||
return -ENOMEM;
|
||||
|
||||
list_add_tail(&p->l_node, rdd->list);
|
||||
rb_link_node(&p->node, parent, newp);
|
||||
rb_insert_color(&p->node, rdd->root);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int ovl_fill_lower(struct ovl_readdir_data *rdd,
|
||||
const char *name, int namelen,
|
||||
loff_t offset, u64 ino, unsigned int d_type)
|
||||
{
|
||||
struct ovl_cache_entry *p;
|
||||
|
||||
p = ovl_cache_entry_find(rdd->root, name, namelen);
|
||||
if (p) {
|
||||
list_move_tail(&p->l_node, rdd->middle);
|
||||
} else {
|
||||
p = ovl_cache_entry_new(name, namelen, ino, d_type);
|
||||
if (p == NULL)
|
||||
rdd->err = -ENOMEM;
|
||||
else
|
||||
list_add_tail(&p->l_node, rdd->middle);
|
||||
}
|
||||
|
||||
return rdd->err;
|
||||
}
|
||||
|
||||
void ovl_cache_free(struct list_head *list)
|
||||
{
|
||||
struct ovl_cache_entry *p;
|
||||
struct ovl_cache_entry *n;
|
||||
|
||||
list_for_each_entry_safe(p, n, list, l_node)
|
||||
kfree(p);
|
||||
|
||||
INIT_LIST_HEAD(list);
|
||||
}
|
||||
|
||||
static void ovl_cache_put(struct ovl_dir_file *od, struct dentry *dentry)
|
||||
{
|
||||
struct ovl_dir_cache *cache = od->cache;
|
||||
|
||||
list_del(&od->cursor.l_node);
|
||||
WARN_ON(cache->refcount <= 0);
|
||||
cache->refcount--;
|
||||
if (!cache->refcount) {
|
||||
if (ovl_dir_cache(dentry) == cache)
|
||||
ovl_set_dir_cache(dentry, NULL);
|
||||
|
||||
ovl_cache_free(&cache->entries);
|
||||
kfree(cache);
|
||||
}
|
||||
}
|
||||
|
||||
static int ovl_fill_merge(void *buf, const char *name, int namelen,
|
||||
loff_t offset, u64 ino, unsigned int d_type)
|
||||
{
|
||||
struct ovl_readdir_data *rdd = buf;
|
||||
|
||||
rdd->count++;
|
||||
if (!rdd->is_merge)
|
||||
return ovl_cache_entry_add_rb(rdd, name, namelen, ino, d_type);
|
||||
else
|
||||
return ovl_fill_lower(rdd, name, namelen, offset, ino, d_type);
|
||||
}
|
||||
|
||||
static inline int ovl_dir_read(struct path *realpath,
|
||||
struct ovl_readdir_data *rdd)
|
||||
{
|
||||
struct file *realfile;
|
||||
int err;
|
||||
|
||||
realfile = ovl_path_open(realpath, O_RDONLY | O_DIRECTORY);
|
||||
if (IS_ERR(realfile))
|
||||
return PTR_ERR(realfile);
|
||||
|
||||
rdd->ctx.pos = 0;
|
||||
do {
|
||||
rdd->count = 0;
|
||||
rdd->err = 0;
|
||||
err = iterate_dir(realfile, &rdd->ctx);
|
||||
if (err >= 0)
|
||||
err = rdd->err;
|
||||
} while (!err && rdd->count);
|
||||
fput(realfile);
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
static void ovl_dir_reset(struct file *file)
|
||||
{
|
||||
struct ovl_dir_file *od = file->private_data;
|
||||
struct ovl_dir_cache *cache = od->cache;
|
||||
struct dentry *dentry = file->f_path.dentry;
|
||||
enum ovl_path_type type = ovl_path_type(dentry);
|
||||
|
||||
if (cache && ovl_dentry_version_get(dentry) != cache->version) {
|
||||
ovl_cache_put(od, dentry);
|
||||
od->cache = NULL;
|
||||
}
|
||||
WARN_ON(!od->is_real && type != OVL_PATH_MERGE);
|
||||
if (od->is_real && type == OVL_PATH_MERGE)
|
||||
od->is_real = false;
|
||||
}
|
||||
|
||||
static int ovl_dir_mark_whiteouts(struct dentry *dir,
|
||||
struct ovl_readdir_data *rdd)
|
||||
{
|
||||
struct ovl_cache_entry *p;
|
||||
struct dentry *dentry;
|
||||
const struct cred *old_cred;
|
||||
struct cred *override_cred;
|
||||
|
||||
override_cred = prepare_creds();
|
||||
if (!override_cred) {
|
||||
ovl_cache_free(rdd->list);
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
/*
|
||||
* CAP_DAC_OVERRIDE for lookup
|
||||
*/
|
||||
cap_raise(override_cred->cap_effective, CAP_DAC_OVERRIDE);
|
||||
old_cred = override_creds(override_cred);
|
||||
|
||||
mutex_lock(&dir->d_inode->i_mutex);
|
||||
list_for_each_entry(p, rdd->list, l_node) {
|
||||
if (!p->name)
|
||||
continue;
|
||||
|
||||
if (p->type != DT_CHR)
|
||||
continue;
|
||||
|
||||
dentry = lookup_one_len(p->name, dir, p->len);
|
||||
if (IS_ERR(dentry))
|
||||
continue;
|
||||
|
||||
p->is_whiteout = ovl_is_whiteout(dentry);
|
||||
dput(dentry);
|
||||
}
|
||||
mutex_unlock(&dir->d_inode->i_mutex);
|
||||
|
||||
revert_creds(old_cred);
|
||||
put_cred(override_cred);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static inline int ovl_dir_read_merged(struct path *upperpath,
|
||||
struct path *lowerpath,
|
||||
struct list_head *list)
|
||||
{
|
||||
int err;
|
||||
struct rb_root root = RB_ROOT;
|
||||
struct list_head middle;
|
||||
struct ovl_readdir_data rdd = {
|
||||
.ctx.actor = ovl_fill_merge,
|
||||
.list = list,
|
||||
.root = &root,
|
||||
.is_merge = false,
|
||||
};
|
||||
|
||||
if (upperpath->dentry) {
|
||||
err = ovl_dir_read(upperpath, &rdd);
|
||||
if (err)
|
||||
goto out;
|
||||
|
||||
if (lowerpath->dentry) {
|
||||
err = ovl_dir_mark_whiteouts(upperpath->dentry, &rdd);
|
||||
if (err)
|
||||
goto out;
|
||||
}
|
||||
}
|
||||
if (lowerpath->dentry) {
|
||||
/*
|
||||
* Insert lowerpath entries before upperpath ones, this allows
|
||||
* offsets to be reasonably constant
|
||||
*/
|
||||
list_add(&middle, rdd.list);
|
||||
rdd.middle = &middle;
|
||||
rdd.is_merge = true;
|
||||
err = ovl_dir_read(lowerpath, &rdd);
|
||||
list_del(&middle);
|
||||
}
|
||||
out:
|
||||
return err;
|
||||
|
||||
}
|
||||
|
||||
static void ovl_seek_cursor(struct ovl_dir_file *od, loff_t pos)
|
||||
{
|
||||
struct ovl_cache_entry *p;
|
||||
loff_t off = 0;
|
||||
|
||||
list_for_each_entry(p, &od->cache->entries, l_node) {
|
||||
if (!p->name)
|
||||
continue;
|
||||
if (off >= pos)
|
||||
break;
|
||||
off++;
|
||||
}
|
||||
list_move_tail(&od->cursor.l_node, &p->l_node);
|
||||
}
|
||||
|
||||
static struct ovl_dir_cache *ovl_cache_get(struct dentry *dentry)
|
||||
{
|
||||
int res;
|
||||
struct path lowerpath;
|
||||
struct path upperpath;
|
||||
struct ovl_dir_cache *cache;
|
||||
|
||||
cache = ovl_dir_cache(dentry);
|
||||
if (cache && ovl_dentry_version_get(dentry) == cache->version) {
|
||||
cache->refcount++;
|
||||
return cache;
|
||||
}
|
||||
ovl_set_dir_cache(dentry, NULL);
|
||||
|
||||
cache = kzalloc(sizeof(struct ovl_dir_cache), GFP_KERNEL);
|
||||
if (!cache)
|
||||
return ERR_PTR(-ENOMEM);
|
||||
|
||||
cache->refcount = 1;
|
||||
INIT_LIST_HEAD(&cache->entries);
|
||||
|
||||
ovl_path_lower(dentry, &lowerpath);
|
||||
ovl_path_upper(dentry, &upperpath);
|
||||
|
||||
res = ovl_dir_read_merged(&upperpath, &lowerpath, &cache->entries);
|
||||
if (res) {
|
||||
ovl_cache_free(&cache->entries);
|
||||
kfree(cache);
|
||||
return ERR_PTR(res);
|
||||
}
|
||||
|
||||
cache->version = ovl_dentry_version_get(dentry);
|
||||
ovl_set_dir_cache(dentry, cache);
|
||||
|
||||
return cache;
|
||||
}
|
||||
|
||||
static int ovl_iterate(struct file *file, struct dir_context *ctx)
|
||||
{
|
||||
struct ovl_dir_file *od = file->private_data;
|
||||
struct dentry *dentry = file->f_path.dentry;
|
||||
|
||||
if (!ctx->pos)
|
||||
ovl_dir_reset(file);
|
||||
|
||||
if (od->is_real)
|
||||
return iterate_dir(od->realfile, ctx);
|
||||
|
||||
if (!od->cache) {
|
||||
struct ovl_dir_cache *cache;
|
||||
|
||||
cache = ovl_cache_get(dentry);
|
||||
if (IS_ERR(cache))
|
||||
return PTR_ERR(cache);
|
||||
|
||||
od->cache = cache;
|
||||
ovl_seek_cursor(od, ctx->pos);
|
||||
}
|
||||
|
||||
while (od->cursor.l_node.next != &od->cache->entries) {
|
||||
struct ovl_cache_entry *p;
|
||||
|
||||
p = list_entry(od->cursor.l_node.next, struct ovl_cache_entry, l_node);
|
||||
/* Skip cursors */
|
||||
if (p->name) {
|
||||
if (!p->is_whiteout) {
|
||||
if (!dir_emit(ctx, p->name, p->len, p->ino, p->type))
|
||||
break;
|
||||
}
|
||||
ctx->pos++;
|
||||
}
|
||||
list_move(&od->cursor.l_node, &p->l_node);
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
static loff_t ovl_dir_llseek(struct file *file, loff_t offset, int origin)
|
||||
{
|
||||
loff_t res;
|
||||
struct ovl_dir_file *od = file->private_data;
|
||||
|
||||
mutex_lock(&file_inode(file)->i_mutex);
|
||||
if (!file->f_pos)
|
||||
ovl_dir_reset(file);
|
||||
|
||||
if (od->is_real) {
|
||||
res = vfs_llseek(od->realfile, offset, origin);
|
||||
file->f_pos = od->realfile->f_pos;
|
||||
} else {
|
||||
res = -EINVAL;
|
||||
|
||||
switch (origin) {
|
||||
case SEEK_CUR:
|
||||
offset += file->f_pos;
|
||||
break;
|
||||
case SEEK_SET:
|
||||
break;
|
||||
default:
|
||||
goto out_unlock;
|
||||
}
|
||||
if (offset < 0)
|
||||
goto out_unlock;
|
||||
|
||||
if (offset != file->f_pos) {
|
||||
file->f_pos = offset;
|
||||
if (od->cache)
|
||||
ovl_seek_cursor(od, offset);
|
||||
}
|
||||
res = offset;
|
||||
}
|
||||
out_unlock:
|
||||
mutex_unlock(&file_inode(file)->i_mutex);
|
||||
|
||||
return res;
|
||||
}
|
||||
|
||||
static int ovl_dir_fsync(struct file *file, loff_t start, loff_t end,
|
||||
int datasync)
|
||||
{
|
||||
struct ovl_dir_file *od = file->private_data;
|
||||
struct dentry *dentry = file->f_path.dentry;
|
||||
struct file *realfile = od->realfile;
|
||||
|
||||
/*
|
||||
* Need to check if we started out being a lower dir, but got copied up
|
||||
*/
|
||||
if (!od->is_upper && ovl_path_type(dentry) == OVL_PATH_MERGE) {
|
||||
struct inode *inode = file_inode(file);
|
||||
|
||||
mutex_lock(&inode->i_mutex);
|
||||
realfile = od->upperfile;
|
||||
if (!realfile) {
|
||||
struct path upperpath;
|
||||
|
||||
ovl_path_upper(dentry, &upperpath);
|
||||
realfile = ovl_path_open(&upperpath, O_RDONLY);
|
||||
if (IS_ERR(realfile)) {
|
||||
mutex_unlock(&inode->i_mutex);
|
||||
return PTR_ERR(realfile);
|
||||
}
|
||||
od->upperfile = realfile;
|
||||
}
|
||||
mutex_unlock(&inode->i_mutex);
|
||||
}
|
||||
|
||||
return vfs_fsync_range(realfile, start, end, datasync);
|
||||
}
|
||||
|
||||
static int ovl_dir_release(struct inode *inode, struct file *file)
|
||||
{
|
||||
struct ovl_dir_file *od = file->private_data;
|
||||
|
||||
if (od->cache) {
|
||||
mutex_lock(&inode->i_mutex);
|
||||
ovl_cache_put(od, file->f_path.dentry);
|
||||
mutex_unlock(&inode->i_mutex);
|
||||
}
|
||||
fput(od->realfile);
|
||||
if (od->upperfile)
|
||||
fput(od->upperfile);
|
||||
kfree(od);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int ovl_dir_open(struct inode *inode, struct file *file)
|
||||
{
|
||||
struct path realpath;
|
||||
struct file *realfile;
|
||||
struct ovl_dir_file *od;
|
||||
enum ovl_path_type type;
|
||||
|
||||
od = kzalloc(sizeof(struct ovl_dir_file), GFP_KERNEL);
|
||||
if (!od)
|
||||
return -ENOMEM;
|
||||
|
||||
type = ovl_path_real(file->f_path.dentry, &realpath);
|
||||
realfile = ovl_path_open(&realpath, file->f_flags);
|
||||
if (IS_ERR(realfile)) {
|
||||
kfree(od);
|
||||
return PTR_ERR(realfile);
|
||||
}
|
||||
INIT_LIST_HEAD(&od->cursor.l_node);
|
||||
od->realfile = realfile;
|
||||
od->is_real = (type != OVL_PATH_MERGE);
|
||||
od->is_upper = (type != OVL_PATH_LOWER);
|
||||
file->private_data = od;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
const struct file_operations ovl_dir_operations = {
|
||||
.read = generic_read_dir,
|
||||
.open = ovl_dir_open,
|
||||
.iterate = ovl_iterate,
|
||||
.llseek = ovl_dir_llseek,
|
||||
.fsync = ovl_dir_fsync,
|
||||
.release = ovl_dir_release,
|
||||
};
|
||||
|
||||
int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list)
|
||||
{
|
||||
int err;
|
||||
struct path lowerpath;
|
||||
struct path upperpath;
|
||||
struct ovl_cache_entry *p;
|
||||
|
||||
ovl_path_upper(dentry, &upperpath);
|
||||
ovl_path_lower(dentry, &lowerpath);
|
||||
|
||||
err = ovl_dir_read_merged(&upperpath, &lowerpath, list);
|
||||
if (err)
|
||||
return err;
|
||||
|
||||
err = 0;
|
||||
|
||||
list_for_each_entry(p, list, l_node) {
|
||||
if (p->is_whiteout)
|
||||
continue;
|
||||
|
||||
if (p->name[0] == '.') {
|
||||
if (p->len == 1)
|
||||
continue;
|
||||
if (p->len == 2 && p->name[1] == '.')
|
||||
continue;
|
||||
}
|
||||
err = -ENOTEMPTY;
|
||||
break;
|
||||
}
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
void ovl_cleanup_whiteouts(struct dentry *upper, struct list_head *list)
|
||||
{
|
||||
struct ovl_cache_entry *p;
|
||||
|
||||
mutex_lock_nested(&upper->d_inode->i_mutex, I_MUTEX_PARENT);
|
||||
list_for_each_entry(p, list, l_node) {
|
||||
struct dentry *dentry;
|
||||
|
||||
if (!p->is_whiteout)
|
||||
continue;
|
||||
|
||||
dentry = lookup_one_len(p->name, upper, p->len);
|
||||
if (IS_ERR(dentry)) {
|
||||
pr_err("overlayfs: lookup '%s/%.*s' failed (%i)\n",
|
||||
upper->d_name.name, p->len, p->name,
|
||||
(int) PTR_ERR(dentry));
|
||||
continue;
|
||||
}
|
||||
ovl_cleanup(upper->d_inode, dentry);
|
||||
dput(dentry);
|
||||
}
|
||||
mutex_unlock(&upper->d_inode->i_mutex);
|
||||
}
|
||||
|
|
@ -0,0 +1,796 @@
|
|||
/*
|
||||
*
|
||||
* Copyright (C) 2011 Novell Inc.
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify it
|
||||
* under the terms of the GNU General Public License version 2 as published by
|
||||
* the Free Software Foundation.
|
||||
*/
|
||||
|
||||
#include <linux/fs.h>
|
||||
#include <linux/namei.h>
|
||||
#include <linux/xattr.h>
|
||||
#include <linux/security.h>
|
||||
#include <linux/mount.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/parser.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/sched.h>
|
||||
#include <linux/statfs.h>
|
||||
#include <linux/seq_file.h>
|
||||
#include "overlayfs.h"
|
||||
|
||||
MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
|
||||
MODULE_DESCRIPTION("Overlay filesystem");
|
||||
MODULE_LICENSE("GPL");
|
||||
|
||||
#define OVERLAYFS_SUPER_MAGIC 0x794c764f
|
||||
|
||||
struct ovl_config {
|
||||
char *lowerdir;
|
||||
char *upperdir;
|
||||
char *workdir;
|
||||
};
|
||||
|
||||
/* private information held for overlayfs's superblock */
|
||||
struct ovl_fs {
|
||||
struct vfsmount *upper_mnt;
|
||||
struct vfsmount *lower_mnt;
|
||||
struct dentry *workdir;
|
||||
long lower_namelen;
|
||||
/* pathnames of lower and upper dirs, for show_options */
|
||||
struct ovl_config config;
|
||||
};
|
||||
|
||||
struct ovl_dir_cache;
|
||||
|
||||
/* private information held for every overlayfs dentry */
|
||||
struct ovl_entry {
|
||||
struct dentry *__upperdentry;
|
||||
struct dentry *lowerdentry;
|
||||
struct ovl_dir_cache *cache;
|
||||
union {
|
||||
struct {
|
||||
u64 version;
|
||||
bool opaque;
|
||||
};
|
||||
struct rcu_head rcu;
|
||||
};
|
||||
};
|
||||
|
||||
const char *ovl_opaque_xattr = "trusted.overlay.opaque";
|
||||
|
||||
|
||||
enum ovl_path_type ovl_path_type(struct dentry *dentry)
|
||||
{
|
||||
struct ovl_entry *oe = dentry->d_fsdata;
|
||||
|
||||
if (oe->__upperdentry) {
|
||||
if (oe->lowerdentry) {
|
||||
if (S_ISDIR(dentry->d_inode->i_mode))
|
||||
return OVL_PATH_MERGE;
|
||||
else
|
||||
return OVL_PATH_UPPER;
|
||||
} else {
|
||||
if (oe->opaque)
|
||||
return OVL_PATH_UPPER;
|
||||
else
|
||||
return OVL_PATH_PURE_UPPER;
|
||||
}
|
||||
} else {
|
||||
return OVL_PATH_LOWER;
|
||||
}
|
||||
}
|
||||
|
||||
static struct dentry *ovl_upperdentry_dereference(struct ovl_entry *oe)
|
||||
{
|
||||
struct dentry *upperdentry = ACCESS_ONCE(oe->__upperdentry);
|
||||
/*
|
||||
* Make sure to order reads to upperdentry wrt ovl_dentry_update()
|
||||
*/
|
||||
smp_read_barrier_depends();
|
||||
return upperdentry;
|
||||
}
|
||||
|
||||
void ovl_path_upper(struct dentry *dentry, struct path *path)
|
||||
{
|
||||
struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
|
||||
struct ovl_entry *oe = dentry->d_fsdata;
|
||||
|
||||
path->mnt = ofs->upper_mnt;
|
||||
path->dentry = ovl_upperdentry_dereference(oe);
|
||||
}
|
||||
|
||||
enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path)
|
||||
{
|
||||
|
||||
enum ovl_path_type type = ovl_path_type(dentry);
|
||||
|
||||
if (type == OVL_PATH_LOWER)
|
||||
ovl_path_lower(dentry, path);
|
||||
else
|
||||
ovl_path_upper(dentry, path);
|
||||
|
||||
return type;
|
||||
}
|
||||
|
||||
struct dentry *ovl_dentry_upper(struct dentry *dentry)
|
||||
{
|
||||
struct ovl_entry *oe = dentry->d_fsdata;
|
||||
|
||||
return ovl_upperdentry_dereference(oe);
|
||||
}
|
||||
|
||||
struct dentry *ovl_dentry_lower(struct dentry *dentry)
|
||||
{
|
||||
struct ovl_entry *oe = dentry->d_fsdata;
|
||||
|
||||
return oe->lowerdentry;
|
||||
}
|
||||
|
||||
struct dentry *ovl_dentry_real(struct dentry *dentry)
|
||||
{
|
||||
struct ovl_entry *oe = dentry->d_fsdata;
|
||||
struct dentry *realdentry;
|
||||
|
||||
realdentry = ovl_upperdentry_dereference(oe);
|
||||
if (!realdentry)
|
||||
realdentry = oe->lowerdentry;
|
||||
|
||||
return realdentry;
|
||||
}
|
||||
|
||||
struct dentry *ovl_entry_real(struct ovl_entry *oe, bool *is_upper)
|
||||
{
|
||||
struct dentry *realdentry;
|
||||
|
||||
realdentry = ovl_upperdentry_dereference(oe);
|
||||
if (realdentry) {
|
||||
*is_upper = true;
|
||||
} else {
|
||||
realdentry = oe->lowerdentry;
|
||||
*is_upper = false;
|
||||
}
|
||||
return realdentry;
|
||||
}
|
||||
|
||||
struct ovl_dir_cache *ovl_dir_cache(struct dentry *dentry)
|
||||
{
|
||||
struct ovl_entry *oe = dentry->d_fsdata;
|
||||
|
||||
return oe->cache;
|
||||
}
|
||||
|
||||
void ovl_set_dir_cache(struct dentry *dentry, struct ovl_dir_cache *cache)
|
||||
{
|
||||
struct ovl_entry *oe = dentry->d_fsdata;
|
||||
|
||||
oe->cache = cache;
|
||||
}
|
||||
|
||||
void ovl_path_lower(struct dentry *dentry, struct path *path)
|
||||
{
|
||||
struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
|
||||
struct ovl_entry *oe = dentry->d_fsdata;
|
||||
|
||||
path->mnt = ofs->lower_mnt;
|
||||
path->dentry = oe->lowerdentry;
|
||||
}
|
||||
|
||||
int ovl_want_write(struct dentry *dentry)
|
||||
{
|
||||
struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
|
||||
return mnt_want_write(ofs->upper_mnt);
|
||||
}
|
||||
|
||||
void ovl_drop_write(struct dentry *dentry)
|
||||
{
|
||||
struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
|
||||
mnt_drop_write(ofs->upper_mnt);
|
||||
}
|
||||
|
||||
struct dentry *ovl_workdir(struct dentry *dentry)
|
||||
{
|
||||
struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
|
||||
return ofs->workdir;
|
||||
}
|
||||
|
||||
bool ovl_dentry_is_opaque(struct dentry *dentry)
|
||||
{
|
||||
struct ovl_entry *oe = dentry->d_fsdata;
|
||||
return oe->opaque;
|
||||
}
|
||||
|
||||
void ovl_dentry_set_opaque(struct dentry *dentry, bool opaque)
|
||||
{
|
||||
struct ovl_entry *oe = dentry->d_fsdata;
|
||||
oe->opaque = opaque;
|
||||
}
|
||||
|
||||
void ovl_dentry_update(struct dentry *dentry, struct dentry *upperdentry)
|
||||
{
|
||||
struct ovl_entry *oe = dentry->d_fsdata;
|
||||
|
||||
WARN_ON(!mutex_is_locked(&upperdentry->d_parent->d_inode->i_mutex));
|
||||
WARN_ON(oe->__upperdentry);
|
||||
BUG_ON(!upperdentry->d_inode);
|
||||
/*
|
||||
* Make sure upperdentry is consistent before making it visible to
|
||||
* ovl_upperdentry_dereference().
|
||||
*/
|
||||
smp_wmb();
|
||||
oe->__upperdentry = upperdentry;
|
||||
}
|
||||
|
||||
void ovl_dentry_version_inc(struct dentry *dentry)
|
||||
{
|
||||
struct ovl_entry *oe = dentry->d_fsdata;
|
||||
|
||||
WARN_ON(!mutex_is_locked(&dentry->d_inode->i_mutex));
|
||||
oe->version++;
|
||||
}
|
||||
|
||||
u64 ovl_dentry_version_get(struct dentry *dentry)
|
||||
{
|
||||
struct ovl_entry *oe = dentry->d_fsdata;
|
||||
|
||||
WARN_ON(!mutex_is_locked(&dentry->d_inode->i_mutex));
|
||||
return oe->version;
|
||||
}
|
||||
|
||||
bool ovl_is_whiteout(struct dentry *dentry)
|
||||
{
|
||||
struct inode *inode = dentry->d_inode;
|
||||
|
||||
return inode && IS_WHITEOUT(inode);
|
||||
}
|
||||
|
||||
static bool ovl_is_opaquedir(struct dentry *dentry)
|
||||
{
|
||||
int res;
|
||||
char val;
|
||||
struct inode *inode = dentry->d_inode;
|
||||
|
||||
if (!S_ISDIR(inode->i_mode) || !inode->i_op->getxattr)
|
||||
return false;
|
||||
|
||||
res = inode->i_op->getxattr(dentry, ovl_opaque_xattr, &val, 1);
|
||||
if (res == 1 && val == 'y')
|
||||
return true;
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
static void ovl_dentry_release(struct dentry *dentry)
|
||||
{
|
||||
struct ovl_entry *oe = dentry->d_fsdata;
|
||||
|
||||
if (oe) {
|
||||
dput(oe->__upperdentry);
|
||||
dput(oe->lowerdentry);
|
||||
kfree_rcu(oe, rcu);
|
||||
}
|
||||
}
|
||||
|
||||
static const struct dentry_operations ovl_dentry_operations = {
|
||||
.d_release = ovl_dentry_release,
|
||||
};
|
||||
|
||||
static struct ovl_entry *ovl_alloc_entry(void)
|
||||
{
|
||||
return kzalloc(sizeof(struct ovl_entry), GFP_KERNEL);
|
||||
}
|
||||
|
||||
static inline struct dentry *ovl_lookup_real(struct dentry *dir,
|
||||
struct qstr *name)
|
||||
{
|
||||
struct dentry *dentry;
|
||||
|
||||
mutex_lock(&dir->d_inode->i_mutex);
|
||||
dentry = lookup_one_len(name->name, dir, name->len);
|
||||
mutex_unlock(&dir->d_inode->i_mutex);
|
||||
|
||||
if (IS_ERR(dentry)) {
|
||||
if (PTR_ERR(dentry) == -ENOENT)
|
||||
dentry = NULL;
|
||||
} else if (!dentry->d_inode) {
|
||||
dput(dentry);
|
||||
dentry = NULL;
|
||||
}
|
||||
return dentry;
|
||||
}
|
||||
|
||||
struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
|
||||
unsigned int flags)
|
||||
{
|
||||
struct ovl_entry *oe;
|
||||
struct dentry *upperdir;
|
||||
struct dentry *lowerdir;
|
||||
struct dentry *upperdentry = NULL;
|
||||
struct dentry *lowerdentry = NULL;
|
||||
struct inode *inode = NULL;
|
||||
int err;
|
||||
|
||||
err = -ENOMEM;
|
||||
oe = ovl_alloc_entry();
|
||||
if (!oe)
|
||||
goto out;
|
||||
|
||||
upperdir = ovl_dentry_upper(dentry->d_parent);
|
||||
lowerdir = ovl_dentry_lower(dentry->d_parent);
|
||||
|
||||
if (upperdir) {
|
||||
upperdentry = ovl_lookup_real(upperdir, &dentry->d_name);
|
||||
err = PTR_ERR(upperdentry);
|
||||
if (IS_ERR(upperdentry))
|
||||
goto out_put_dir;
|
||||
|
||||
if (lowerdir && upperdentry) {
|
||||
if (ovl_is_whiteout(upperdentry)) {
|
||||
dput(upperdentry);
|
||||
upperdentry = NULL;
|
||||
oe->opaque = true;
|
||||
} else if (ovl_is_opaquedir(upperdentry)) {
|
||||
oe->opaque = true;
|
||||
}
|
||||
}
|
||||
}
|
||||
if (lowerdir && !oe->opaque) {
|
||||
lowerdentry = ovl_lookup_real(lowerdir, &dentry->d_name);
|
||||
err = PTR_ERR(lowerdentry);
|
||||
if (IS_ERR(lowerdentry))
|
||||
goto out_dput_upper;
|
||||
}
|
||||
|
||||
if (lowerdentry && upperdentry &&
|
||||
(!S_ISDIR(upperdentry->d_inode->i_mode) ||
|
||||
!S_ISDIR(lowerdentry->d_inode->i_mode))) {
|
||||
dput(lowerdentry);
|
||||
lowerdentry = NULL;
|
||||
oe->opaque = true;
|
||||
}
|
||||
|
||||
if (lowerdentry || upperdentry) {
|
||||
struct dentry *realdentry;
|
||||
|
||||
realdentry = upperdentry ? upperdentry : lowerdentry;
|
||||
err = -ENOMEM;
|
||||
inode = ovl_new_inode(dentry->d_sb, realdentry->d_inode->i_mode,
|
||||
oe);
|
||||
if (!inode)
|
||||
goto out_dput;
|
||||
ovl_copyattr(realdentry->d_inode, inode);
|
||||
}
|
||||
|
||||
oe->__upperdentry = upperdentry;
|
||||
oe->lowerdentry = lowerdentry;
|
||||
|
||||
dentry->d_fsdata = oe;
|
||||
d_add(dentry, inode);
|
||||
|
||||
return NULL;
|
||||
|
||||
out_dput:
|
||||
dput(lowerdentry);
|
||||
out_dput_upper:
|
||||
dput(upperdentry);
|
||||
out_put_dir:
|
||||
kfree(oe);
|
||||
out:
|
||||
return ERR_PTR(err);
|
||||
}
|
||||
|
||||
struct file *ovl_path_open(struct path *path, int flags)
|
||||
{
|
||||
return dentry_open(path, flags, current_cred());
|
||||
}
|
||||
|
||||
static void ovl_put_super(struct super_block *sb)
|
||||
{
|
||||
struct ovl_fs *ufs = sb->s_fs_info;
|
||||
|
||||
dput(ufs->workdir);
|
||||
mntput(ufs->upper_mnt);
|
||||
mntput(ufs->lower_mnt);
|
||||
|
||||
kfree(ufs->config.lowerdir);
|
||||
kfree(ufs->config.upperdir);
|
||||
kfree(ufs->config.workdir);
|
||||
kfree(ufs);
|
||||
}
|
||||
|
||||
/**
|
||||
* ovl_statfs
|
||||
* @sb: The overlayfs super block
|
||||
* @buf: The struct kstatfs to fill in with stats
|
||||
*
|
||||
* Get the filesystem statistics. As writes always target the upper layer
|
||||
* filesystem pass the statfs to the same filesystem.
|
||||
*/
|
||||
static int ovl_statfs(struct dentry *dentry, struct kstatfs *buf)
|
||||
{
|
||||
struct ovl_fs *ofs = dentry->d_sb->s_fs_info;
|
||||
struct dentry *root_dentry = dentry->d_sb->s_root;
|
||||
struct path path;
|
||||
int err;
|
||||
|
||||
ovl_path_upper(root_dentry, &path);
|
||||
|
||||
err = vfs_statfs(&path, buf);
|
||||
if (!err) {
|
||||
buf->f_namelen = max(buf->f_namelen, ofs->lower_namelen);
|
||||
buf->f_type = OVERLAYFS_SUPER_MAGIC;
|
||||
}
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
/**
|
||||
* ovl_show_options
|
||||
*
|
||||
* Prints the mount options for a given superblock.
|
||||
* Returns zero; does not fail.
|
||||
*/
|
||||
static int ovl_show_options(struct seq_file *m, struct dentry *dentry)
|
||||
{
|
||||
struct super_block *sb = dentry->d_sb;
|
||||
struct ovl_fs *ufs = sb->s_fs_info;
|
||||
|
||||
seq_printf(m, ",lowerdir=%s", ufs->config.lowerdir);
|
||||
seq_printf(m, ",upperdir=%s", ufs->config.upperdir);
|
||||
seq_printf(m, ",workdir=%s", ufs->config.workdir);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct super_operations ovl_super_operations = {
|
||||
.put_super = ovl_put_super,
|
||||
.statfs = ovl_statfs,
|
||||
.show_options = ovl_show_options,
|
||||
};
|
||||
|
||||
enum {
|
||||
OPT_LOWERDIR,
|
||||
OPT_UPPERDIR,
|
||||
OPT_WORKDIR,
|
||||
OPT_ERR,
|
||||
};
|
||||
|
||||
static const match_table_t ovl_tokens = {
|
||||
{OPT_LOWERDIR, "lowerdir=%s"},
|
||||
{OPT_UPPERDIR, "upperdir=%s"},
|
||||
{OPT_WORKDIR, "workdir=%s"},
|
||||
{OPT_ERR, NULL}
|
||||
};
|
||||
|
||||
static int ovl_parse_opt(char *opt, struct ovl_config *config)
|
||||
{
|
||||
char *p;
|
||||
|
||||
while ((p = strsep(&opt, ",")) != NULL) {
|
||||
int token;
|
||||
substring_t args[MAX_OPT_ARGS];
|
||||
|
||||
if (!*p)
|
||||
continue;
|
||||
|
||||
token = match_token(p, ovl_tokens, args);
|
||||
switch (token) {
|
||||
case OPT_UPPERDIR:
|
||||
kfree(config->upperdir);
|
||||
config->upperdir = match_strdup(&args[0]);
|
||||
if (!config->upperdir)
|
||||
return -ENOMEM;
|
||||
break;
|
||||
|
||||
case OPT_LOWERDIR:
|
||||
kfree(config->lowerdir);
|
||||
config->lowerdir = match_strdup(&args[0]);
|
||||
if (!config->lowerdir)
|
||||
return -ENOMEM;
|
||||
break;
|
||||
|
||||
case OPT_WORKDIR:
|
||||
kfree(config->workdir);
|
||||
config->workdir = match_strdup(&args[0]);
|
||||
if (!config->workdir)
|
||||
return -ENOMEM;
|
||||
break;
|
||||
|
||||
default:
|
||||
return -EINVAL;
|
||||
}
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
#define OVL_WORKDIR_NAME "work"
|
||||
|
||||
static struct dentry *ovl_workdir_create(struct vfsmount *mnt,
|
||||
struct dentry *dentry)
|
||||
{
|
||||
struct inode *dir = dentry->d_inode;
|
||||
struct dentry *work;
|
||||
int err;
|
||||
bool retried = false;
|
||||
|
||||
err = mnt_want_write(mnt);
|
||||
if (err)
|
||||
return ERR_PTR(err);
|
||||
|
||||
mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
|
||||
retry:
|
||||
work = lookup_one_len(OVL_WORKDIR_NAME, dentry,
|
||||
strlen(OVL_WORKDIR_NAME));
|
||||
|
||||
if (!IS_ERR(work)) {
|
||||
struct kstat stat = {
|
||||
.mode = S_IFDIR | 0,
|
||||
};
|
||||
|
||||
if (work->d_inode) {
|
||||
err = -EEXIST;
|
||||
if (retried)
|
||||
goto out_dput;
|
||||
|
||||
retried = true;
|
||||
ovl_cleanup(dir, work);
|
||||
dput(work);
|
||||
goto retry;
|
||||
}
|
||||
|
||||
err = ovl_create_real(dir, work, &stat, NULL, NULL, true);
|
||||
if (err)
|
||||
goto out_dput;
|
||||
}
|
||||
out_unlock:
|
||||
mutex_unlock(&dir->i_mutex);
|
||||
mnt_drop_write(mnt);
|
||||
|
||||
return work;
|
||||
|
||||
out_dput:
|
||||
dput(work);
|
||||
work = ERR_PTR(err);
|
||||
goto out_unlock;
|
||||
}
|
||||
|
||||
static int ovl_mount_dir(const char *name, struct path *path)
|
||||
{
|
||||
int err;
|
||||
|
||||
err = kern_path(name, LOOKUP_FOLLOW, path);
|
||||
if (err) {
|
||||
pr_err("overlayfs: failed to resolve '%s': %i\n", name, err);
|
||||
err = -EINVAL;
|
||||
}
|
||||
return err;
|
||||
}
|
||||
|
||||
static bool ovl_is_allowed_fs_type(struct dentry *root)
|
||||
{
|
||||
const struct dentry_operations *dop = root->d_op;
|
||||
|
||||
/*
|
||||
* We don't support:
|
||||
* - automount filesystems
|
||||
* - filesystems with revalidate (FIXME for lower layer)
|
||||
* - filesystems with case insensitive names
|
||||
*/
|
||||
if (dop &&
|
||||
(dop->d_manage || dop->d_automount ||
|
||||
dop->d_revalidate || dop->d_weak_revalidate ||
|
||||
dop->d_compare || dop->d_hash)) {
|
||||
return false;
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
/* Workdir should not be subdir of upperdir and vice versa */
|
||||
static bool ovl_workdir_ok(struct dentry *workdir, struct dentry *upperdir)
|
||||
{
|
||||
bool ok = false;
|
||||
|
||||
if (workdir != upperdir) {
|
||||
ok = (lock_rename(workdir, upperdir) == NULL);
|
||||
unlock_rename(workdir, upperdir);
|
||||
}
|
||||
return ok;
|
||||
}
|
||||
|
||||
static int ovl_fill_super(struct super_block *sb, void *data, int silent)
|
||||
{
|
||||
struct path lowerpath;
|
||||
struct path upperpath;
|
||||
struct path workpath;
|
||||
struct inode *root_inode;
|
||||
struct dentry *root_dentry;
|
||||
struct ovl_entry *oe;
|
||||
struct ovl_fs *ufs;
|
||||
struct kstatfs statfs;
|
||||
int err;
|
||||
|
||||
err = -ENOMEM;
|
||||
ufs = kzalloc(sizeof(struct ovl_fs), GFP_KERNEL);
|
||||
if (!ufs)
|
||||
goto out;
|
||||
|
||||
err = ovl_parse_opt((char *) data, &ufs->config);
|
||||
if (err)
|
||||
goto out_free_config;
|
||||
|
||||
/* FIXME: workdir is not needed for a R/O mount */
|
||||
err = -EINVAL;
|
||||
if (!ufs->config.upperdir || !ufs->config.lowerdir ||
|
||||
!ufs->config.workdir) {
|
||||
pr_err("overlayfs: missing upperdir or lowerdir or workdir\n");
|
||||
goto out_free_config;
|
||||
}
|
||||
|
||||
err = -ENOMEM;
|
||||
oe = ovl_alloc_entry();
|
||||
if (oe == NULL)
|
||||
goto out_free_config;
|
||||
|
||||
err = ovl_mount_dir(ufs->config.upperdir, &upperpath);
|
||||
if (err)
|
||||
goto out_free_oe;
|
||||
|
||||
err = ovl_mount_dir(ufs->config.lowerdir, &lowerpath);
|
||||
if (err)
|
||||
goto out_put_upperpath;
|
||||
|
||||
err = ovl_mount_dir(ufs->config.workdir, &workpath);
|
||||
if (err)
|
||||
goto out_put_lowerpath;
|
||||
|
||||
err = -EINVAL;
|
||||
if (!S_ISDIR(upperpath.dentry->d_inode->i_mode) ||
|
||||
!S_ISDIR(lowerpath.dentry->d_inode->i_mode) ||
|
||||
!S_ISDIR(workpath.dentry->d_inode->i_mode)) {
|
||||
pr_err("overlayfs: upperdir or lowerdir or workdir not a directory\n");
|
||||
goto out_put_workpath;
|
||||
}
|
||||
|
||||
if (upperpath.mnt != workpath.mnt) {
|
||||
pr_err("overlayfs: workdir and upperdir must reside under the same mount\n");
|
||||
goto out_put_workpath;
|
||||
}
|
||||
if (!ovl_workdir_ok(workpath.dentry, upperpath.dentry)) {
|
||||
pr_err("overlayfs: workdir and upperdir must be separate subtrees\n");
|
||||
goto out_put_workpath;
|
||||
}
|
||||
|
||||
if (!ovl_is_allowed_fs_type(upperpath.dentry)) {
|
||||
pr_err("overlayfs: filesystem of upperdir is not supported\n");
|
||||
goto out_put_workpath;
|
||||
}
|
||||
|
||||
if (!ovl_is_allowed_fs_type(lowerpath.dentry)) {
|
||||
pr_err("overlayfs: filesystem of lowerdir is not supported\n");
|
||||
goto out_put_workpath;
|
||||
}
|
||||
|
||||
err = vfs_statfs(&lowerpath, &statfs);
|
||||
if (err) {
|
||||
pr_err("overlayfs: statfs failed on lowerpath\n");
|
||||
goto out_put_workpath;
|
||||
}
|
||||
ufs->lower_namelen = statfs.f_namelen;
|
||||
|
||||
sb->s_stack_depth = max(upperpath.mnt->mnt_sb->s_stack_depth,
|
||||
lowerpath.mnt->mnt_sb->s_stack_depth) + 1;
|
||||
|
||||
err = -EINVAL;
|
||||
if (sb->s_stack_depth > FILESYSTEM_MAX_STACK_DEPTH) {
|
||||
pr_err("overlayfs: maximum fs stacking depth exceeded\n");
|
||||
goto out_put_workpath;
|
||||
}
|
||||
|
||||
ufs->upper_mnt = clone_private_mount(&upperpath);
|
||||
err = PTR_ERR(ufs->upper_mnt);
|
||||
if (IS_ERR(ufs->upper_mnt)) {
|
||||
pr_err("overlayfs: failed to clone upperpath\n");
|
||||
goto out_put_workpath;
|
||||
}
|
||||
|
||||
ufs->lower_mnt = clone_private_mount(&lowerpath);
|
||||
err = PTR_ERR(ufs->lower_mnt);
|
||||
if (IS_ERR(ufs->lower_mnt)) {
|
||||
pr_err("overlayfs: failed to clone lowerpath\n");
|
||||
goto out_put_upper_mnt;
|
||||
}
|
||||
|
||||
ufs->workdir = ovl_workdir_create(ufs->upper_mnt, workpath.dentry);
|
||||
err = PTR_ERR(ufs->workdir);
|
||||
if (IS_ERR(ufs->workdir)) {
|
||||
pr_err("overlayfs: failed to create directory %s/%s\n",
|
||||
ufs->config.workdir, OVL_WORKDIR_NAME);
|
||||
goto out_put_lower_mnt;
|
||||
}
|
||||
|
||||
/*
|
||||
* Make lower_mnt R/O. That way fchmod/fchown on lower file
|
||||
* will fail instead of modifying lower fs.
|
||||
*/
|
||||
ufs->lower_mnt->mnt_flags |= MNT_READONLY;
|
||||
|
||||
/* If the upper fs is r/o, we mark overlayfs r/o too */
|
||||
if (ufs->upper_mnt->mnt_sb->s_flags & MS_RDONLY)
|
||||
sb->s_flags |= MS_RDONLY;
|
||||
|
||||
sb->s_d_op = &ovl_dentry_operations;
|
||||
|
||||
err = -ENOMEM;
|
||||
root_inode = ovl_new_inode(sb, S_IFDIR, oe);
|
||||
if (!root_inode)
|
||||
goto out_put_workdir;
|
||||
|
||||
root_dentry = d_make_root(root_inode);
|
||||
if (!root_dentry)
|
||||
goto out_put_workdir;
|
||||
|
||||
mntput(upperpath.mnt);
|
||||
mntput(lowerpath.mnt);
|
||||
path_put(&workpath);
|
||||
|
||||
oe->__upperdentry = upperpath.dentry;
|
||||
oe->lowerdentry = lowerpath.dentry;
|
||||
|
||||
root_dentry->d_fsdata = oe;
|
||||
|
||||
sb->s_magic = OVERLAYFS_SUPER_MAGIC;
|
||||
sb->s_op = &ovl_super_operations;
|
||||
sb->s_root = root_dentry;
|
||||
sb->s_fs_info = ufs;
|
||||
|
||||
return 0;
|
||||
|
||||
out_put_workdir:
|
||||
dput(ufs->workdir);
|
||||
out_put_lower_mnt:
|
||||
mntput(ufs->lower_mnt);
|
||||
out_put_upper_mnt:
|
||||
mntput(ufs->upper_mnt);
|
||||
out_put_workpath:
|
||||
path_put(&workpath);
|
||||
out_put_lowerpath:
|
||||
path_put(&lowerpath);
|
||||
out_put_upperpath:
|
||||
path_put(&upperpath);
|
||||
out_free_oe:
|
||||
kfree(oe);
|
||||
out_free_config:
|
||||
kfree(ufs->config.lowerdir);
|
||||
kfree(ufs->config.upperdir);
|
||||
kfree(ufs->config.workdir);
|
||||
kfree(ufs);
|
||||
out:
|
||||
return err;
|
||||
}
|
||||
|
||||
static struct dentry *ovl_mount(struct file_system_type *fs_type, int flags,
|
||||
const char *dev_name, void *raw_data)
|
||||
{
|
||||
return mount_nodev(fs_type, flags, raw_data, ovl_fill_super);
|
||||
}
|
||||
|
||||
static struct file_system_type ovl_fs_type = {
|
||||
.owner = THIS_MODULE,
|
||||
.name = "overlayfs",
|
||||
.mount = ovl_mount,
|
||||
.kill_sb = kill_anon_super,
|
||||
};
|
||||
MODULE_ALIAS_FS("overlayfs");
|
||||
|
||||
static int __init ovl_init(void)
|
||||
{
|
||||
return register_filesystem(&ovl_fs_type);
|
||||
}
|
||||
|
||||
static void __exit ovl_exit(void)
|
||||
{
|
||||
unregister_filesystem(&ovl_fs_type);
|
||||
}
|
||||
|
||||
module_init(ovl_init);
|
||||
module_exit(ovl_exit);
|
||||
|
|
@ -1330,6 +1330,7 @@ long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
|
|||
|
||||
return ret;
|
||||
}
|
||||
EXPORT_SYMBOL(do_splice_direct);
|
||||
|
||||
static int splice_pipe_to_pipe(struct pipe_inode_info *ipipe,
|
||||
struct pipe_inode_info *opipe,
|
||||
|
|
|
|||
|
|
@ -222,6 +222,13 @@ typedef void (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
|
|||
#define ATTR_OPEN (1 << 15) /* Truncating from open(O_TRUNC) */
|
||||
#define ATTR_TIMES_SET (1 << 16)
|
||||
|
||||
/*
|
||||
* Whiteout is represented by a char device. The following constants define the
|
||||
* mode and device number to use.
|
||||
*/
|
||||
#define WHITEOUT_MODE 0
|
||||
#define WHITEOUT_DEV 0
|
||||
|
||||
/*
|
||||
* This is the Inode Attributes structure, used for notify_change(). It
|
||||
* uses the above definitions as flags, to know which values have changed.
|
||||
|
|
@ -254,6 +261,12 @@ struct iattr {
|
|||
*/
|
||||
#include <linux/quota.h>
|
||||
|
||||
/*
|
||||
* Maximum number of layers of fs stack. Needs to be limited to
|
||||
* prevent kernel stack overflow
|
||||
*/
|
||||
#define FILESYSTEM_MAX_STACK_DEPTH 2
|
||||
|
||||
/**
|
||||
* enum positive_aop_returns - aop return codes with specific semantics
|
||||
*
|
||||
|
|
@ -1266,6 +1279,11 @@ struct super_block {
|
|||
struct list_lru s_dentry_lru ____cacheline_aligned_in_smp;
|
||||
struct list_lru s_inode_lru ____cacheline_aligned_in_smp;
|
||||
struct rcu_head rcu;
|
||||
|
||||
/*
|
||||
* Indicates how deep in a filesystem stack this SB is
|
||||
*/
|
||||
int s_stack_depth;
|
||||
};
|
||||
|
||||
extern struct timespec current_fs_time(struct super_block *sb);
|
||||
|
|
@ -1398,6 +1416,7 @@ extern int vfs_link(struct dentry *, struct inode *, struct dentry *, struct ino
|
|||
extern int vfs_rmdir(struct inode *, struct dentry *);
|
||||
extern int vfs_unlink(struct inode *, struct dentry *, struct inode **);
|
||||
extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct dentry *, struct inode **, unsigned int);
|
||||
extern int vfs_whiteout(struct inode *, struct dentry *);
|
||||
|
||||
/*
|
||||
* VFS dentry helper functions.
|
||||
|
|
@ -1528,6 +1547,9 @@ struct inode_operations {
|
|||
umode_t create_mode, int *opened);
|
||||
int (*tmpfile) (struct inode *, struct dentry *, umode_t);
|
||||
int (*set_acl)(struct inode *, struct posix_acl *, int);
|
||||
|
||||
/* WARNING: probably going away soon, do not use! */
|
||||
int (*dentry_open)(struct dentry *, struct file *, const struct cred *);
|
||||
} ____cacheline_aligned;
|
||||
|
||||
ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
|
||||
|
|
@ -1625,6 +1647,9 @@ struct super_operations {
|
|||
#define IS_AUTOMOUNT(inode) ((inode)->i_flags & S_AUTOMOUNT)
|
||||
#define IS_NOSEC(inode) ((inode)->i_flags & S_NOSEC)
|
||||
|
||||
#define IS_WHITEOUT(inode) (S_ISCHR(inode->i_mode) && \
|
||||
(inode)->i_rdev == WHITEOUT_DEV)
|
||||
|
||||
/*
|
||||
* Inode state bits. Protected by inode->i_lock
|
||||
*
|
||||
|
|
@ -2040,6 +2065,7 @@ extern struct file *file_open_name(struct filename *, int, umode_t);
|
|||
extern struct file *filp_open(const char *, int, umode_t);
|
||||
extern struct file *file_open_root(struct dentry *, struct vfsmount *,
|
||||
const char *, int);
|
||||
extern int vfs_open(const struct path *, struct file *, const struct cred *);
|
||||
extern struct file * dentry_open(const struct path *, int, const struct cred *);
|
||||
extern int filp_close(struct file *, fl_owner_t id);
|
||||
|
||||
|
|
@ -2253,7 +2279,9 @@ extern sector_t bmap(struct inode *, sector_t);
|
|||
#endif
|
||||
extern int notify_change(struct dentry *, struct iattr *, struct inode **);
|
||||
extern int inode_permission(struct inode *, int);
|
||||
extern int __inode_permission(struct inode *, int);
|
||||
extern int generic_permission(struct inode *, int);
|
||||
extern int __check_sticky(struct inode *dir, struct inode *inode);
|
||||
|
||||
static inline bool execute_ok(struct inode *inode)
|
||||
{
|
||||
|
|
@ -2452,6 +2480,9 @@ extern ssize_t iter_file_splice_write(struct pipe_inode_info *,
|
|||
struct file *, loff_t *, size_t, unsigned int);
|
||||
extern ssize_t generic_splice_sendpage(struct pipe_inode_info *pipe,
|
||||
struct file *out, loff_t *, size_t len, unsigned int flags);
|
||||
extern long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
|
||||
loff_t *opos, size_t len, unsigned int flags);
|
||||
|
||||
|
||||
extern void
|
||||
file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
|
||||
|
|
@ -2737,6 +2768,14 @@ static inline int is_sxid(umode_t mode)
|
|||
return (mode & S_ISUID) || ((mode & S_ISGID) && (mode & S_IXGRP));
|
||||
}
|
||||
|
||||
static inline int check_sticky(struct inode *dir, struct inode *inode)
|
||||
{
|
||||
if (!(dir->i_mode & S_ISVTX))
|
||||
return 0;
|
||||
|
||||
return __check_sticky(dir, inode);
|
||||
}
|
||||
|
||||
static inline void inode_has_no_xattr(struct inode *inode)
|
||||
{
|
||||
if (!is_sxid(inode->i_mode) && (inode->i_sb->s_flags & MS_NOSEC))
|
||||
|
|
|
|||
|
|
@ -81,6 +81,9 @@ extern struct vfsmount *mntget(struct vfsmount *mnt);
|
|||
extern struct vfsmount *mnt_clone_internal(struct path *path);
|
||||
extern int __mnt_is_readonly(struct vfsmount *mnt);
|
||||
|
||||
struct path;
|
||||
extern struct vfsmount *clone_private_mount(struct path *path);
|
||||
|
||||
struct file_system_type;
|
||||
extern struct vfsmount *vfs_kern_mount(struct file_system_type *type,
|
||||
int flags, const char *name,
|
||||
|
|
|
|||
|
|
@ -37,6 +37,7 @@
|
|||
|
||||
#define RENAME_NOREPLACE (1 << 0) /* Don't overwrite target */
|
||||
#define RENAME_EXCHANGE (1 << 1) /* Exchange source and dest */
|
||||
#define RENAME_WHITEOUT (1 << 2) /* Whiteout source */
|
||||
|
||||
struct fstrim_range {
|
||||
__u64 start;
|
||||
|
|
|
|||
36
mm/shmem.c
36
mm/shmem.c
|
|
@ -2345,6 +2345,32 @@ static int shmem_exchange(struct inode *old_dir, struct dentry *old_dentry, stru
|
|||
return 0;
|
||||
}
|
||||
|
||||
static int shmem_whiteout(struct inode *old_dir, struct dentry *old_dentry)
|
||||
{
|
||||
struct dentry *whiteout;
|
||||
int error;
|
||||
|
||||
whiteout = d_alloc(old_dentry->d_parent, &old_dentry->d_name);
|
||||
if (!whiteout)
|
||||
return -ENOMEM;
|
||||
|
||||
error = shmem_mknod(old_dir, whiteout,
|
||||
S_IFCHR | WHITEOUT_MODE, WHITEOUT_DEV);
|
||||
dput(whiteout);
|
||||
if (error)
|
||||
return error;
|
||||
|
||||
/*
|
||||
* Cheat and hash the whiteout while the old dentry is still in
|
||||
* place, instead of playing games with FS_RENAME_DOES_D_MOVE.
|
||||
*
|
||||
* d_lookup() will consistently find one of them at this point,
|
||||
* not sure which one, but that isn't even important.
|
||||
*/
|
||||
d_rehash(whiteout);
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* The VFS layer already does all the dentry stuff for rename,
|
||||
* we just have to decrement the usage count for the target if
|
||||
|
|
@ -2356,7 +2382,7 @@ static int shmem_rename2(struct inode *old_dir, struct dentry *old_dentry, struc
|
|||
struct inode *inode = old_dentry->d_inode;
|
||||
int they_are_dirs = S_ISDIR(inode->i_mode);
|
||||
|
||||
if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
|
||||
if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
|
||||
return -EINVAL;
|
||||
|
||||
if (flags & RENAME_EXCHANGE)
|
||||
|
|
@ -2365,6 +2391,14 @@ static int shmem_rename2(struct inode *old_dir, struct dentry *old_dentry, struc
|
|||
if (!simple_empty(new_dentry))
|
||||
return -ENOTEMPTY;
|
||||
|
||||
if (flags & RENAME_WHITEOUT) {
|
||||
int error;
|
||||
|
||||
error = shmem_whiteout(old_dir, old_dentry);
|
||||
if (error)
|
||||
return error;
|
||||
}
|
||||
|
||||
if (new_dentry->d_inode) {
|
||||
(void) shmem_unlink(new_dir, new_dentry);
|
||||
if (they_are_dirs) {
|
||||
|
|
|
|||
Loading…
Reference in New Issue