static int
zpl_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
{
boolean_t issnap = ITOZSB(dentry->d_inode)->z_issnap;
int error;
/*
* Ensure MNT_SHRINKABLE is set on snapshots to ensure they are
* unmounted automatically with the parent file system. This
* is done on the first getattr because it's not easy to get the
* vfsmount structure at mount time. This call path is explicitly
* marked unlikely to avoid any performance impact. FWIW, ext4
* resorts to a similar trick for sysadmin convenience.
*/
if (unlikely(issnap && !(mnt->mnt_flags & MNT_SHRINKABLE)))
mnt->mnt_flags |= MNT_SHRINKABLE;
error = -zfs_getattr_fast(dentry->d_inode, stat);
ASSERT3S(error, <=, 0);
return (error);
}
/* ARGSUSED */
int
zfsctl_snapdir_remove(struct inode *dip, char *name, cred_t *cr, int flags)
{
zfs_sb_t *zsb = ITOZSB(dip);
char *snapname, *real;
int error;
ZFS_ENTER(zsb);
snapname = kmem_alloc(MAXNAMELEN, KM_SLEEP);
real = kmem_alloc(MAXNAMELEN, KM_SLEEP);
if (zsb->z_case == ZFS_CASE_INSENSITIVE) {
error = dmu_snapshot_realname(zsb->z_os, name, real,
MAXNAMELEN, NULL);
if (error == 0) {
name = real;
} else if (error != ENOTSUP) {
goto out;
}
}
error = zfsctl_snapshot_zname(dip, name, MAXNAMELEN, snapname);
if (!error)
error = zfs_secpolicy_destroy_perms(snapname, cr);
if (error)
goto out;
error = zfsctl_unmount_snapshot(zsb, name, MNT_FORCE);
if ((error == 0) || (error == ENOENT))
error = dmu_objset_destroy(snapname, B_FALSE);
out:
kmem_free(snapname, MAXNAMELEN);
kmem_free(real, MAXNAMELEN);
ZFS_EXIT(zsb);
return (error);
}
static int
__zpl_xattr_acl_set_default(struct inode *ip, const char *name,
const void *value, size_t size, int flags)
{
struct posix_acl *acl;
int type = ACL_TYPE_DEFAULT;
int error = 0;
/* xattr_resolve_name will do this for us if this is defined */
#ifndef HAVE_XATTR_HANDLER_NAME
if (strcmp(name, "") != 0)
return (-EINVAL);
#endif
if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIXACL)
return (-EOPNOTSUPP);
if (!zpl_inode_owner_or_capable(ip))
return (-EPERM);
if (value) {
acl = zpl_acl_from_xattr(value, size);
if (IS_ERR(acl))
return (PTR_ERR(acl));
else if (acl) {
error = zpl_posix_acl_valid(ip, acl);
if (error) {
zpl_posix_acl_release(acl);
return (error);
}
}
} else {
acl = NULL;
}
error = zpl_set_acl(ip, acl, type);
zpl_posix_acl_release(acl);
return (error);
}
/*
* When a .zfs/snapshot/<snapshot> inode is evicted they must be removed
* from the snapshot list. This will normally happen as part of the auto
* unmount, however in the case of a manual snapshot unmount this will be
* the only notification we receive.
*/
void
zfsctl_snapdir_inactive(struct inode *ip)
{
zfs_sb_t *zsb = ITOZSB(ip);
zfs_snapentry_t *sep, *next;
mutex_enter(&zsb->z_ctldir_lock);
sep = avl_first(&zsb->z_ctldir_snaps);
while (sep != NULL) {
next = AVL_NEXT(&zsb->z_ctldir_snaps, sep);
if (sep->se_inode == ip) {
avl_remove(&zsb->z_ctldir_snaps, sep);
taskq_cancel_id(zfs_expire_taskq, sep->se_taskqid);
zfsctl_sep_free(sep);
break;
}
sep = next;
}
mutex_exit(&zsb->z_ctldir_lock);
}
int
zpl_chmod_acl(struct inode *ip)
{
struct posix_acl *acl;
int error;
if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIXACL)
return (0);
if (S_ISLNK(ip->i_mode))
return (-EOPNOTSUPP);
acl = zpl_get_acl(ip, ACL_TYPE_ACCESS);
if (IS_ERR(acl) || !acl)
return (PTR_ERR(acl));
error = posix_acl_chmod(&acl,GFP_KERNEL, ip->i_mode);
if (!error)
error = zpl_set_acl(ip,ACL_TYPE_ACCESS, acl);
zpl_posix_acl_release(acl);
return (error);
}
static int
zpl_xattr_filldir(xattr_filldir_t *xf, const char *name, int name_len)
{
if (!strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN))
if (!(ITOZSB(xf->inode)->z_flags & ZSB_XATTR))
return (0);
if (!strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN))
if (!capable(CAP_SYS_ADMIN))
return (0);
/* When xf->buf is NULL only calculate the required size. */
if (xf->buf) {
if (xf->offset + name_len + 1 > xf->size)
return (-ERANGE);
memcpy(xf->buf + xf->offset, name, name_len);
xf->buf[xf->offset + name_len] = '\0';
}
xf->offset += (name_len + 1);
return (0);
}
int
zfsctl_mount_snapshot(struct path *path, int flags)
{
struct dentry *dentry = path->dentry;
struct inode *ip = dentry->d_inode;
zfs_sb_t *zsb = ITOZSB(ip);
char *full_name, *full_path;
zfs_snapentry_t *sep;
zfs_snapentry_t search;
char *argv[] = { "/bin/sh", "-c", NULL, NULL };
char *envp[] = { NULL };
int error;
ZFS_ENTER(zsb);
full_name = kmem_zalloc(MAXNAMELEN, KM_SLEEP);
full_path = kmem_zalloc(PATH_MAX, KM_SLEEP);
error = zfsctl_snapshot_zname(ip, dname(dentry), MAXNAMELEN, full_name);
if (error)
goto error;
error = zfsctl_snapshot_zpath(path, PATH_MAX, full_path);
if (error)
goto error;
/*
* Attempt to mount the snapshot from user space. Normally this
* would be done using the vfs_kern_mount() function, however that
* function is marked GPL-only and cannot be used. On error we
* careful to log the real error to the console and return EISDIR
* to safely abort the automount. This should be very rare.
*/
argv[2] = kmem_asprintf(SET_MOUNT_CMD, full_name, full_path);
error = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC);
strfree(argv[2]);
if (error) {
printk("ZFS: Unable to automount %s at %s: %d\n",
full_name, full_path, error);
error = EISDIR;
goto error;
}
mutex_enter(&zsb->z_ctldir_lock);
/*
* Ensure a previous entry does not exist, if it does safely remove
* it any cancel the outstanding expiration. This can occur when a
* snapshot is manually unmounted and then an automount is triggered.
*/
search.se_name = full_name;
sep = avl_find(&zsb->z_ctldir_snaps, &search, NULL);
if (sep) {
avl_remove(&zsb->z_ctldir_snaps, sep);
taskq_cancel_id(zfs_expire_taskq, sep->se_taskqid);
zfsctl_sep_free(sep);
}
sep = zfsctl_sep_alloc();
sep->se_name = full_name;
sep->se_path = full_path;
sep->se_inode = ip;
avl_add(&zsb->z_ctldir_snaps, sep);
sep->se_taskqid = taskq_dispatch_delay(zfs_expire_taskq,
zfsctl_expire_snapshot, sep, TQ_SLEEP,
ddi_get_lbolt() + zfs_expire_snapshot * HZ);
mutex_exit(&zsb->z_ctldir_lock);
error:
if (error) {
kmem_free(full_name, MAXNAMELEN);
kmem_free(full_path, PATH_MAX);
}
ZFS_EXIT(zsb);
return (error);
}
/*ARGSUSED*/
int
zfsctl_snapdir_rename(struct inode *sdip, char *sname,
struct inode *tdip, char *tname, cred_t *cr, int flags)
{
zfs_sb_t *zsb = ITOZSB(sdip);
zfs_snapentry_t search, *sep;
avl_index_t where;
char *to, *from, *real;
int error;
ZFS_ENTER(zsb);
to = kmem_alloc(MAXNAMELEN, KM_SLEEP);
from = kmem_alloc(MAXNAMELEN, KM_SLEEP);
real = kmem_alloc(MAXNAMELEN, KM_SLEEP);
if (zsb->z_case == ZFS_CASE_INSENSITIVE) {
error = dmu_snapshot_realname(zsb->z_os, sname, real,
MAXNAMELEN, NULL);
if (error == 0) {
sname = real;
} else if (error != ENOTSUP) {
goto out;
}
}
error = zfsctl_snapshot_zname(sdip, sname, MAXNAMELEN, from);
if (!error)
error = zfsctl_snapshot_zname(tdip, tname, MAXNAMELEN, to);
if (!error)
error = zfs_secpolicy_rename_perms(from, to, cr);
if (error)
goto out;
/*
* Cannot move snapshots out of the snapdir.
*/
if (sdip != tdip) {
error = EINVAL;
goto out;
}
/*
* No-op when names are identical.
*/
if (strcmp(sname, tname) == 0) {
error = 0;
goto out;
}
mutex_enter(&zsb->z_ctldir_lock);
error = dmu_objset_rename(from, to, B_FALSE);
if (error)
goto out_unlock;
search.se_name = (char *)sname;
sep = avl_find(&zsb->z_ctldir_snaps, &search, &where);
if (sep)
zfsctl_rename_snap(zsb, sep, tname);
out_unlock:
mutex_exit(&zsb->z_ctldir_lock);
out:
kmem_free(from, MAXNAMELEN);
kmem_free(to, MAXNAMELEN);
kmem_free(real, MAXNAMELEN);
ZFS_EXIT(zsb);
return (error);
}
int
zpl_set_acl(struct inode *ip, int type, struct posix_acl *acl)
{
struct super_block *sb = ITOZSB(ip)->z_sb;
char *name, *value = NULL;
int error = 0;
size_t size = 0;
if (S_ISLNK(ip->i_mode))
return (-EOPNOTSUPP);
switch(type) {
case ACL_TYPE_ACCESS:
name = POSIX_ACL_XATTR_ACCESS;
if (acl) {
zpl_equivmode_t mode = ip->i_mode;
error = posix_acl_equiv_mode(acl, &mode);
if (error < 0) {
return (error);
} else {
/*
* The mode bits will have been set by
* ->zfs_setattr()->zfs_acl_chmod_setattr()
* using the ZFS ACL conversion. If they
* differ from the Posix ACL conversion dirty
* the inode to write the Posix mode bits.
*/
if (ip->i_mode != mode) {
ip->i_mode = mode;
ip->i_ctime = current_fs_time(sb);
mark_inode_dirty(ip);
}
if (error == 0)
acl = NULL;
}
}
break;
case ACL_TYPE_DEFAULT:
name = POSIX_ACL_XATTR_DEFAULT;
if (!S_ISDIR(ip->i_mode))
return (acl ? -EACCES : 0);
break;
default:
return (-EINVAL);
}
if (acl) {
size = posix_acl_xattr_size(acl->a_count);
value = kmem_alloc(size, KM_SLEEP);
error = zpl_acl_to_xattr(acl, value, size);
if (error < 0) {
kmem_free(value, size);
return (error);
}
}
error = zpl_xattr_set(ip, name, value, size, 0);
if (value)
kmem_free(value, size);
if (!error) {
if (acl)
zpl_set_cached_acl(ip, type, acl);
else
zpl_forget_cached_acl(ip, type);
}
return (error);
}
/*
* Extended user attributes
*
* "Extended user attributes may be assigned to files and directories for
* storing arbitrary additional information such as the mime type,
* character set or encoding of a file. The access permissions for user
* attributes are defined by the file permission bits: read permission
* is required to retrieve the attribute value, and writer permission is
* required to change it.
*
* The file permission bits of regular files and directories are
* interpreted differently from the file permission bits of special
* files and symbolic links. For regular files and directories the file
* permission bits define access to the file's contents, while for
* device special files they define access to the device described by
* the special file. The file permissions of symbolic links are not
* used in access checks. These differences would allow users to
* consume filesystem resources in a way not controllable by disk quotas
* for group or world writable special files and directories.
*
* For this reason, extended user attributes are allowed only for
* regular files and directories, and access to extended user attributes
* is restricted to the owner and to users with appropriate capabilities
* for directories with the sticky bit set (see the chmod(1) manual page
* for an explanation of the sticky bit)." - xattr(7)
*
* ZFS allows extended user attributes to be disabled administratively
* by setting the 'xattr=off' property on the dataset.
*/
static int
__zpl_xattr_user_list(struct inode *ip, char *list, size_t list_size,
const char *name, size_t name_len)
{
return (ITOZSB(ip)->z_flags & ZSB_XATTR);
}
