[RFC][PATCH 29/42] __shmem_file_setup(): reorder allocations

[Al Viro]

From: Al Viro <v...@zeniv.linux.org.uk>

grab inode and reserve memory first.

Signed-off-by: Al Viro <v...@zeniv.linux.org.uk>
---
 mm/shmem.c | 43 ++++++++++++++++++++-----------------------
 1 file changed, 20 insertions(+), 23 deletions(-)

diff --git a/mm/shmem.c b/mm/shmem.c
index 2cab84403055..1146a48926bc 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -3918,41 +3918,38 @@ static struct file *__shmem_file_setup(struct vfsmount 
*mnt, const char *name, l
        if (shmem_acct_size(flags, size))
                return ERR_PTR(-ENOMEM);
 
-       res = ERR_PTR(-ENOMEM);
+       sb = mnt->mnt_sb;
+       inode = shmem_get_inode(sb, NULL, S_IFREG | S_IRWXUGO, 0, flags);
+       if (unlikely(!inode)) {
+               shmem_unacct_size(flags, size);
+               return ERR_PTR(-ENOSPC);
+       }
+       inode->i_flags |= i_flags;
+       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 */
-       sb = mnt->mnt_sb;
        path.mnt = mntget(mnt);
        path.dentry = d_alloc_pseudo(sb, &this);
-       if (!path.dentry)
-               goto put_memory;
+       if (!path.dentry) {
+               iput(inode);
+               return ERR_PTR(-ENOMEM);
+       }
        d_set_d_op(path.dentry, &anon_ops);
 
-       res = ERR_PTR(-ENOSPC);
-       inode = shmem_get_inode(sb, NULL, S_IFREG | 0777, 0, flags);
-       if (!inode)
-               goto put_memory;
-
-       inode->i_flags |= i_flags;
        d_instantiate(path.dentry, inode);
-       inode->i_size = size;
-       clear_nlink(inode);     /* It is unlinked */
-       res = ERR_PTR(ramfs_nommu_expand_for_mapping(inode, size));
-       if (IS_ERR(res))
-               goto put_path;
 
        res = alloc_file(&path, FMODE_WRITE | FMODE_READ,
                  &shmem_file_operations);
        if (IS_ERR(res))
-               goto put_path;
-
-       return res;
-
-put_memory:
-       shmem_unacct_size(flags, size);
-put_path:
-       path_put(&path);
+               path_put(&path);
        return res;
 }
 
-- 
2.11.0