[ 34/98] saner proc_get_inode() calling conventions

From: Greg Kroah-Hartman
Date: Tue Mar 26 2013 - 19:41:00 EST


3.8-stable review patch. If anyone has any objections, please let me know.

------------------

From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

commit d3d009cb965eae7e002ea5badf603ea8f4c34915 upstream.

Make it drop the pde in *all* cases when no new reference to it is
put into an inode - both when an inode had already been set up
(as we were already doing) and when inode allocation has failed.
Makes for simpler logics in callers...

Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Dave Jones <davej@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/proc/generic.c | 21 +++++++--------------
fs/proc/inode.c | 10 +++-------
2 files changed, 10 insertions(+), 21 deletions(-)

--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -412,8 +412,7 @@ static const struct dentry_operations pr
struct dentry *proc_lookup_de(struct proc_dir_entry *de, struct inode *dir,
struct dentry *dentry)
{
- struct inode *inode = NULL;
- int error = -ENOENT;
+ struct inode *inode;

spin_lock(&proc_subdir_lock);
for (de = de->subdir; de ; de = de->next) {
@@ -422,22 +421,16 @@ struct dentry *proc_lookup_de(struct pro
if (!memcmp(dentry->d_name.name, de->name, de->namelen)) {
pde_get(de);
spin_unlock(&proc_subdir_lock);
- error = -ENOMEM;
inode = proc_get_inode(dir->i_sb, de);
- goto out_unlock;
+ if (!inode)
+ return ERR_PTR(-ENOMEM);
+ d_set_d_op(dentry, &proc_dentry_operations);
+ d_add(dentry, inode);
+ return NULL;
}
}
spin_unlock(&proc_subdir_lock);
-out_unlock:
-
- if (inode) {
- d_set_d_op(dentry, &proc_dentry_operations);
- d_add(dentry, inode);
- return NULL;
- }
- if (de)
- pde_put(de);
- return ERR_PTR(error);
+ return ERR_PTR(-ENOENT);
}

struct dentry *proc_lookup(struct inode *dir, struct dentry *dentry,
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -445,12 +445,9 @@ static const struct file_operations proc

struct inode *proc_get_inode(struct super_block *sb, struct proc_dir_entry *de)
{
- struct inode * inode;
+ struct inode *inode = iget_locked(sb, de->low_ino);

- inode = iget_locked(sb, de->low_ino);
- if (!inode)
- return NULL;
- if (inode->i_state & I_NEW) {
+ if (inode && (inode->i_state & I_NEW)) {
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
PROC_I(inode)->pde = de;

@@ -482,7 +479,7 @@ struct inode *proc_get_inode(struct supe
} else
pde_put(de);
return inode;
-}
+}

int proc_fill_super(struct super_block *s)
{
@@ -499,6 +496,5 @@ int proc_fill_super(struct super_block *
return 0;

printk("proc_read_super: get root inode failed\n");
- pde_put(&proc_root);
return -ENOMEM;
}


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