[PATCH v7 25/49] vfs: fix mknodat to retry on ESTALE errors

Jeff Layton
2012-10-02T00:17:42Z

fs/namei.c | 43 +++++++++++++++++++++++++------------------
1 file changed, 25 insertions(+), 18 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c
index 6c75fc1..ac62973 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3180,34 +3180,41 @@ SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode,
struct dentry *dentry;
struct path path;
int error;
+ unsigned int try = 0;

error = may_mknod(mode);
if (error)
return error;

- dentry = user_path_create(dfd, filename, &path, false, false);
- if (IS_ERR(dentry))
- return PTR_ERR(dentry);
+ do {
+ dentry = user_path_create(dfd, filename, &path, false, try);
+ if (IS_ERR(dentry))
+ return PTR_ERR(dentry);

- if (!IS_POSIXACL(path.dentry->d_inode))
- mode &= ~current_umask();
- error = security_path_mknod(&path, dentry, mode, dev);
- if (error)
- goto out;
- switch (mode & S_IFMT) {
- case 0: case S_IFREG:
- error = vfs_create(path.dentry->d_inode,dentry,mode,true);
+ if (!IS_POSIXACL(path.dentry->d_inode))
+ mode &= ~current_umask();
+ error = security_path_mknod(&path, dentry, mode, dev);
+ if (error)
+ goto out;
+ switch (mode & S_IFMT) {
+ case 0:
+ case S_IFREG:
+ error = vfs_create(path.dentry->d_inode, dentry,
+ mode, true);
break;
- case S_IFCHR: case S_IFBLK:
- error = vfs_mknod(path.dentry->d_inode,dentry,mode,
+ case S_IFCHR:
+ case S_IFBLK:
+ error = vfs_mknod(path.dentry->d_inode, dentry, mode,
new_decode_dev(dev));
break;
- case S_IFIFO: case S_IFSOCK:
- error = vfs_mknod(path.dentry->d_inode,dentry,mode,0);
- break;
- }
+ case S_IFIFO:
+ case S_IFSOCK:
+ error = vfs_mknod(path.dentry->d_inode, dentry,
+ mode, 0);
+ }
out:
- done_path_create(&path, dentry);
+ done_path_create(&path, dentry);
+ } while (retry_estale(error, try++));
return error;
}

--
1.7.11.4