IOMMU, AMD Family15h Model10-1Fh erratum 746 Workaround

[firefly-linux-kernel-4.4.55.git] / fs / stat.c

diff --git a/fs/stat.c b/fs/stat.c
index eae494630a36507e03defe8bdf836ee6b337b4ee..14f45459c83d650fb09c4069d5dd7db907a67b95 100644 (file)
--- a/fs/stat.c
+++ b/fs/stat.c
@@ -74,7 +74,7 @@ int vfs_fstatat(int dfd, const char __user *filename, struct kstat *stat,
 {
        struct path path;
        int error = -EINVAL;
-       int lookup_flags = 0;
+       unsigned int lookup_flags = 0;
 
        if ((flag & ~(AT_SYMLINK_NOFOLLOW | AT_NO_AUTOMOUNT |
                      AT_EMPTY_PATH)) != 0)
@@ -84,13 +84,17 @@ int vfs_fstatat(int dfd, const char __user *filename, struct kstat *stat,
                lookup_flags |= LOOKUP_FOLLOW;
        if (flag & AT_EMPTY_PATH)
                lookup_flags |= LOOKUP_EMPTY;
-
+retry:
        error = user_path_at(dfd, filename, lookup_flags, &path);
        if (error)
                goto out;
 
        error = vfs_getattr(path.mnt, path.dentry, stat);
        path_put(&path);
+       if (retry_estale(error, lookup_flags)) {
+               lookup_flags |= LOOKUP_REVAL;
+               goto retry;
+       }
 out:
        return error;
 }
@@ -296,11 +300,13 @@ SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
        struct path path;
        int error;
        int empty = 0;
+       unsigned int lookup_flags = LOOKUP_EMPTY;
 
        if (bufsiz <= 0)
                return -EINVAL;
 
-       error = user_path_at_empty(dfd, pathname, LOOKUP_EMPTY, &path, &empty);
+retry:
+       error = user_path_at_empty(dfd, pathname, lookup_flags, &path, &empty);
        if (!error) {
                struct inode *inode = path.dentry->d_inode;
 
@@ -314,6 +320,10 @@ SYSCALL_DEFINE4(readlinkat, int, dfd, const char __user *, pathname,
                        }
                }
                path_put(&path);
+               if (retry_estale(error, lookup_flags)) {
+                       lookup_flags |= LOOKUP_REVAL;
+                       goto retry;
+               }
        }
        return error;
 }