Revert "Revert "ANDROID: vfs: add d_canonical_path for stacked filesystem support""

This reverts commit fc411cf98a.

For sdcardfs.

Signed-off-by: Tao Huang <huangtao@rock-chips.com>
Change-Id: I56fd2ee1acda8664548055c4b9ce14a3cb3233ce
This commit is contained in:
Tao Huang
2020-09-24 19:52:02 +08:00
parent ebf16f78d6
commit f9cb1a06e3
3 changed files with 21 additions and 3 deletions

View File

@ -702,6 +702,8 @@ SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname,
struct fsnotify_group *group;
struct inode *inode;
struct path path;
struct path alteredpath;
struct path *canonical_path = &path;
struct fd f;
int ret;
unsigned flags = 0;
@ -747,13 +749,22 @@ SYSCALL_DEFINE3(inotify_add_watch, int, fd, const char __user *, pathname,
if (ret)
goto fput_and_out;
/* support stacked filesystems */
if(path.dentry && path.dentry->d_op) {
if (path.dentry->d_op->d_canonical_path) {
path.dentry->d_op->d_canonical_path(&path, &alteredpath);
canonical_path = &alteredpath;
path_put(&path);
}
}
/* inode held in place by reference to path; group by fget on fd */
inode = path.dentry->d_inode;
inode = canonical_path->dentry->d_inode;
group = f.file->private_data;
/* create/update an inode mark */
ret = inotify_update_watch(group, inode, mask);
path_put(&path);
path_put(canonical_path);
fput_and_out:
fdput(f);
return ret;

View File

@ -150,7 +150,7 @@ struct dentry_operations {
struct vfsmount *(*d_automount)(struct path *);
int (*d_manage)(const struct path *, bool);
struct dentry *(*d_real)(struct dentry *, const struct inode *);
void (*d_canonical_path)(const struct path *, struct path *);
ANDROID_KABI_RESERVE(1);
ANDROID_KABI_RESERVE(2);
ANDROID_KABI_RESERVE(3);

View File

@ -210,12 +210,19 @@ static inline void fsnotify_modify(struct file *file)
static inline void fsnotify_open(struct file *file)
{
const struct path *path = &file->f_path;
struct path lower_path;
struct inode *inode = file_inode(file);
__u32 mask = FS_OPEN;
if (S_ISDIR(inode->i_mode))
mask |= FS_ISDIR;
if (path->dentry->d_op && path->dentry->d_op->d_canonical_path) {
path->dentry->d_op->d_canonical_path(path, &lower_path);
fsnotify_parent(&lower_path, NULL, mask);
fsnotify(lower_path.dentry->d_inode, mask, &lower_path, FSNOTIFY_EVENT_PATH, NULL, 0);
path_put(&lower_path);
}
fsnotify_parent(path, NULL, mask);
fsnotify(inode, mask, path, FSNOTIFY_EVENT_PATH, NULL, 0);
}