[RFC][PATCH 30/42] ... and switch shmem_file_setup() to alloc_file_pseudo()

From: Al Viro
Date: Tue Jul 10 2018 - 22:22:13 EST


From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
mm/shmem.c | 39 ++++++++-------------------------------
1 file changed, 8 insertions(+), 31 deletions(-)

diff --git a/mm/shmem.c b/mm/shmem.c
index 1146a48926bc..fd21df189f32 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -3896,18 +3896,11 @@ EXPORT_SYMBOL_GPL(shmem_truncate_range);

/* common code */

-static const struct dentry_operations anon_ops = {
- .d_dname = simple_dname
-};
-
static struct file *__shmem_file_setup(struct vfsmount *mnt, const char *name, loff_t size,
unsigned long flags, unsigned int i_flags)
{
- struct file *res;
struct inode *inode;
- struct path path;
- struct super_block *sb;
- struct qstr this;
+ struct file *res;

if (IS_ERR(mnt))
return ERR_CAST(mnt);
@@ -3918,8 +3911,8 @@ static struct file *__shmem_file_setup(struct vfsmount *mnt, const char *name, l
if (shmem_acct_size(flags, size))
return ERR_PTR(-ENOMEM);

- sb = mnt->mnt_sb;
- inode = shmem_get_inode(sb, NULL, S_IFREG | S_IRWXUGO, 0, flags);
+ inode = shmem_get_inode(mnt->mnt_sb, NULL, S_IFREG | S_IRWXUGO, 0,
+ flags);
if (unlikely(!inode)) {
shmem_unacct_size(flags, size);
return ERR_PTR(-ENOSPC);
@@ -3928,28 +3921,12 @@ static struct file *__shmem_file_setup(struct vfsmount *mnt, const char *name, l
inode->i_size = size;
clear_nlink(inode); /* It is unlinked */
res = ERR_PTR(ramfs_nommu_expand_for_mapping(inode, size));
- if (IS_ERR(res)) {
- iput(inode);
- return res;
- }
-
- this.name = name;
- this.len = strlen(name);
- this.hash = 0; /* will go */
- path.mnt = mntget(mnt);
- path.dentry = d_alloc_pseudo(sb, &this);
- if (!path.dentry) {
- iput(inode);
- return ERR_PTR(-ENOMEM);
- }
- d_set_d_op(path.dentry, &anon_ops);
-
- d_instantiate(path.dentry, inode);
-
- res = alloc_file(&path, FMODE_WRITE | FMODE_READ,
- &shmem_file_operations);
+ if (!IS_ERR(res))
+ res = alloc_file_pseudo(inode, mnt, name,
+ FMODE_WRITE | FMODE_READ,
+ &shmem_file_operations);
if (IS_ERR(res))
- path_put(&path);
+ iput(inode);
return res;
}

--
2.11.0