[PATCH 1/3] shmem: fix double uncharge in __shmem_file_setup()

Konstantin Khlebnikov
2014-06-24T20:16:13Z

If __shmem_file_setup() fails on struct file allocation it uncharges memory
commitment twice: first by shmem_unacct_size() and second time implicitly in
shmem_evict_inode() when it kills newly created inode.
This patch removes shmem_unacct_size() from error path if inode already here.

Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
---
mm/shmem.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/mm/shmem.c b/mm/shmem.c
index 8f419cf..0aabcbd 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2895,16 +2895,16 @@ static struct file *__shmem_file_setup(const char *name, loff_t size,
this.len = strlen(name);
this.hash = 0; /* will go */
sb = shm_mnt->mnt_sb;
+ path.mnt = mntget(shm_mnt);
path.dentry = d_alloc_pseudo(sb, &this);
if (!path.dentry)
goto put_memory;
d_set_d_op(path.dentry, &anon_ops);
- path.mnt = mntget(shm_mnt);

res = ERR_PTR(-ENOSPC);
inode = shmem_get_inode(sb, NULL, S_IFREG | S_IRWXUGO, 0, flags);
if (!inode)
- goto put_dentry;
+ goto put_memory;

inode->i_flags |= i_flags;
d_instantiate(path.dentry, inode);
@@ -2912,19 +2912,19 @@ static struct file *__shmem_file_setup(const char *name, loff_t size,
clear_nlink(inode); /* It is unlinked */
res = ERR_PTR(ramfs_nommu_expand_for_mapping(inode, size));
if (IS_ERR(res))
- goto put_dentry;
+ goto put_path;

res = alloc_file(&path, FMODE_WRITE | FMODE_READ,
&shmem_file_operations);
if (IS_ERR(res))
- goto put_dentry;
+ goto put_path;

return res;

-put_dentry:
- path_put(&path);
put_memory:
shmem_unacct_size(flags, size);
+put_path:
+ path_put(&path);
return res;
}