xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

kernfs: don't set dentry->d_fsdata

Browse Source 
When working on adding exportfs operations in kernfs, I found it's hard
to initialize dentry->d_fsdata in the exportfs operations. Looks there
is no way to do it without race condition. Look at the kernfs code
closely, there is no point to set dentry->d_fsdata. inode->i_private
already points to kernfs_node, and we can get inode from a dentry. So
this patch just delete the d_fsdata usage.

Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Shaohua Li
2017-07-12 11:49:49 -07:00
committed by Jens Axboe
parent ba16b2846a
commit 319ba91d35
6 changed files with 27 additions and 31 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
fs/kernfs/mount.c
View File

@@ -33,7 +33,7 @@ static int kernfs_sop_remount_fs(struct super_block *sb, int *flags, char *data)
static int kernfs_sop_show_options(struct seq_file *sf, struct dentry *dentry)
{
struct kernfs_root *root = kernfs_root(dentry->d_fsdata);
struct kernfs_root *root = kernfs_root(kernfs_dentry_node(dentry));
struct kernfs_syscall_ops *scops = root->syscall_ops;
if (scops && scops->show_options)
@@ -43,7 +43,7 @@ static int kernfs_sop_show_options(struct seq_file *sf, struct dentry *dentry)
static int kernfs_sop_show_path(struct seq_file *sf, struct dentry *dentry)
{
struct kernfs_node *node = dentry->d_fsdata;
struct kernfs_node *node = kernfs_dentry_node(dentry);
struct kernfs_root *root = kernfs_root(node);
struct kernfs_syscall_ops *scops = root->syscall_ops;
@@ -176,8 +176,6 @@ static int kernfs_fill_super(struct super_block *sb, unsigned long magic)
pr_debug("%s: could not get root dentry!\n", __func__);
return -ENOMEM;
}
kernfs_get(info->root->kn);
root->d_fsdata = info->root->kn;
sb->s_root = root;
sb->s_d_op = &kernfs_dops;
return 0;
@@ -283,7 +281,6 @@ struct dentry *kernfs_mount_ns(struct file_system_type *fs_type, int flags,
void kernfs_kill_sb(struct super_block *sb)
{
struct kernfs_super_info *info = kernfs_info(sb);
struct kernfs_node *root_kn = sb->s_root->d_fsdata;
mutex_lock(&kernfs_mutex);
list_del(&info->node);
@@ -295,7 +292,6 @@ void kernfs_kill_sb(struct super_block *sb)
*/
kill_anon_super(sb);
kfree(info);
kernfs_put(root_kn);
}
/**