kernfs: introduce kernfs_node_id

inode number and generation can identify a kernfs node. We are going to
export the identification by exportfs operations, so put ino and
generation into a separate structure. It's convenient when later patches
use the identification.

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 11:49:50 -07:00 committed by Jens Axboe
parent 319ba91d35
commit c53cd490b1
6 changed files with 21 additions and 13 deletions

View File

@ -539,7 +539,7 @@ void kernfs_put(struct kernfs_node *kn)
}
kfree(kn->iattr);
spin_lock(&kernfs_idr_lock);
idr_remove(&root->ino_idr, kn->ino);
idr_remove(&root->ino_idr, kn->id.ino);
spin_unlock(&kernfs_idr_lock);
kmem_cache_free(kernfs_node_cache, kn);
@ -645,8 +645,8 @@ static struct kernfs_node *__kernfs_new_node(struct kernfs_root *root,
idr_preload_end();
if (ret < 0)
goto err_out2;
kn->ino = ret;
kn->generation = gen;
kn->id.ino = ret;
kn->id.generation = gen;
/*
* set ino first. This barrier is paired with atomic_inc_not_zero in
@ -721,7 +721,7 @@ struct kernfs_node *kernfs_find_and_get_node_by_ino(struct kernfs_root *root,
* before 'count'. So if 'count' is uptodate, 'ino' should be uptodate,
* hence we can use 'ino' to filter stale node.
*/
if (kn->ino != ino)
if (kn->id.ino != ino)
goto out;
rcu_read_unlock();
@ -1654,7 +1654,7 @@ static int kernfs_fop_readdir(struct file *file, struct dir_context *ctx)
const char *name = pos->name;
unsigned int type = dt_type(pos);
int len = strlen(name);
ino_t ino = pos->ino;
ino_t ino = pos->id.ino;
ctx->pos = pos->hash;
file->private_data = pos;

View File

@ -895,7 +895,7 @@ repeat:
* have the matching @file available. Look up the inodes
* and generate the events manually.
*/
inode = ilookup(info->sb, kn->ino);
inode = ilookup(info->sb, kn->id.ino);
if (!inode)
continue;
@ -903,7 +903,7 @@ repeat:
if (parent) {
struct inode *p_inode;
p_inode = ilookup(info->sb, parent->ino);
p_inode = ilookup(info->sb, parent->id.ino);
if (p_inode) {
fsnotify(p_inode, FS_MODIFY | FS_EVENT_ON_CHILD,
inode, FSNOTIFY_EVENT_INODE, kn->name, 0);

View File

@ -220,7 +220,7 @@ static void kernfs_init_inode(struct kernfs_node *kn, struct inode *inode)
inode->i_private = kn;
inode->i_mapping->a_ops = &kernfs_aops;
inode->i_op = &kernfs_iops;
inode->i_generation = kn->generation;
inode->i_generation = kn->id.generation;
set_default_inode_attr(inode, kn->mode);
kernfs_refresh_inode(kn, inode);
@ -266,7 +266,7 @@ struct inode *kernfs_get_inode(struct super_block *sb, struct kernfs_node *kn)
{
struct inode *inode;
inode = iget_locked(sb, kn->ino);
inode = iget_locked(sb, kn->id.ino);
if (inode && (inode->i_state & I_NEW))
kernfs_init_inode(kn, inode);

View File

@ -543,7 +543,7 @@ static inline bool cgroup_is_populated(struct cgroup *cgrp)
/* returns ino associated with a cgroup */
static inline ino_t cgroup_ino(struct cgroup *cgrp)
{
return cgrp->kn->ino;
return cgrp->kn->id.ino;
}
/* cft/css accessors for cftype->write() operation */

View File

@ -95,6 +95,15 @@ struct kernfs_elem_attr {
struct kernfs_node *notify_next; /* for kernfs_notify() */
};
/* represent a kernfs node */
union kernfs_node_id {
struct {
u32 ino;
u32 generation;
};
u64 id;
};
/*
* kernfs_node - the building block of kernfs hierarchy. Each and every
* kernfs node is represented by single kernfs_node. Most fields are
@ -131,11 +140,10 @@ struct kernfs_node {
void *priv;
union kernfs_node_id id;
unsigned short flags;
umode_t mode;
unsigned int ino;
struct kernfs_iattrs *iattr;
u32 generation;
};
/*

View File

@ -136,7 +136,7 @@ DEFINE_EVENT(writeback_dirty_inode_template, writeback_dirty_inode,
static inline unsigned int __trace_wb_assign_cgroup(struct bdi_writeback *wb)
{
return wb->memcg_css->cgroup->kn->ino;
return wb->memcg_css->cgroup->kn->id.ino;
}
static inline unsigned int __trace_wbc_assign_cgroup(struct writeback_control *wbc)