Merge tag 'writeback_for_v5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git...

[linux-2.6-microblaze.git] / fs / xattr.c

diff --git a/fs/xattr.c b/fs/xattr.c
index 91608d9..386b456 100644 (file)
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -134,6 +134,33 @@ xattr_permission(struct inode *inode, const char *name, int mask)
        return inode_permission(inode, mask);
 }
 
+/*
+ * Look for any handler that deals with the specified namespace.
+ */
+int
+xattr_supported_namespace(struct inode *inode, const char *prefix)
+{
+       const struct xattr_handler **handlers = inode->i_sb->s_xattr;
+       const struct xattr_handler *handler;
+       size_t preflen;
+
+       if (!(inode->i_opflags & IOP_XATTR)) {
+               if (unlikely(is_bad_inode(inode)))
+                       return -EIO;
+               return -EOPNOTSUPP;
+       }
+
+       preflen = strlen(prefix);
+
+       for_each_xattr_handler(handlers, handler) {
+               if (!strncmp(xattr_prefix(handler), prefix, preflen))
+                       return 0;
+       }
+
+       return -EOPNOTSUPP;
+}
+EXPORT_SYMBOL(xattr_supported_namespace);
+
 int
 __vfs_setxattr(struct dentry *dentry, struct inode *inode, const char *name,
               const void *value, size_t size, int flags)
@@ -204,10 +231,22 @@ int __vfs_setxattr_noperm(struct dentry *dentry, const char *name,
        return error;
 }
 
-
+/**
+ * __vfs_setxattr_locked: set an extended attribute while holding the inode
+ * lock
+ *
+ *  @dentry - object to perform setxattr on
+ *  @name - xattr name to set
+ *  @value - value to set @name to
+ *  @size - size of @value
+ *  @flags - flags to pass into filesystem operations
+ *  @delegated_inode - on return, will contain an inode pointer that
+ *  a delegation was broken on, NULL if none.
+ */
 int
-vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
-               size_t size, int flags)
+__vfs_setxattr_locked(struct dentry *dentry, const char *name,
+               const void *value, size_t size, int flags,
+               struct inode **delegated_inode)
 {
        struct inode *inode = dentry->d_inode;
        int error;
@@ -216,15 +255,40 @@ vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
        if (error)
                return error;
 
-       inode_lock(inode);
        error = security_inode_setxattr(dentry, name, value, size, flags);
        if (error)
                goto out;
 
+       error = try_break_deleg(inode, delegated_inode);
+       if (error)
+               goto out;
+
        error = __vfs_setxattr_noperm(dentry, name, value, size, flags);
 
 out:
+       return error;
+}
+EXPORT_SYMBOL_GPL(__vfs_setxattr_locked);
+
+int
+vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
+               size_t size, int flags)
+{
+       struct inode *inode = dentry->d_inode;
+       struct inode *delegated_inode = NULL;
+       int error;
+
+retry_deleg:
+       inode_lock(inode);
+       error = __vfs_setxattr_locked(dentry, name, value, size, flags,
+           &delegated_inode);
        inode_unlock(inode);
+
+       if (delegated_inode) {
+               error = break_deleg_wait(&delegated_inode);
+               if (!error)
+                       goto retry_deleg;
+       }
        return error;
 }
 EXPORT_SYMBOL_GPL(vfs_setxattr);
@@ -378,8 +442,18 @@ __vfs_removexattr(struct dentry *dentry, const char *name)
 }
 EXPORT_SYMBOL(__vfs_removexattr);
 
+/**
+ * __vfs_removexattr_locked: set an extended attribute while holding the inode
+ * lock
+ *
+ *  @dentry - object to perform setxattr on
+ *  @name - name of xattr to remove
+ *  @delegated_inode - on return, will contain an inode pointer that
+ *  a delegation was broken on, NULL if none.
+ */
 int
-vfs_removexattr(struct dentry *dentry, const char *name)
+__vfs_removexattr_locked(struct dentry *dentry, const char *name,
+               struct inode **delegated_inode)
 {
        struct inode *inode = dentry->d_inode;
        int error;
@@ -388,11 +462,14 @@ vfs_removexattr(struct dentry *dentry, const char *name)
        if (error)
                return error;
 
-       inode_lock(inode);
        error = security_inode_removexattr(dentry, name);
        if (error)
                goto out;
 
+       error = try_break_deleg(inode, delegated_inode);
+       if (error)
+               goto out;
+
        error = __vfs_removexattr(dentry, name);
 
        if (!error) {
@@ -401,12 +478,32 @@ vfs_removexattr(struct dentry *dentry, const char *name)
        }
 
 out:
+       return error;
+}
+EXPORT_SYMBOL_GPL(__vfs_removexattr_locked);
+
+int
+vfs_removexattr(struct dentry *dentry, const char *name)
+{
+       struct inode *inode = dentry->d_inode;
+       struct inode *delegated_inode = NULL;
+       int error;
+
+retry_deleg:
+       inode_lock(inode);
+       error = __vfs_removexattr_locked(dentry, name, &delegated_inode);
        inode_unlock(inode);
+
+       if (delegated_inode) {
+               error = break_deleg_wait(&delegated_inode);
+               if (!error)
+                       goto retry_deleg;
+       }
+
        return error;
 }
 EXPORT_SYMBOL_GPL(vfs_removexattr);
 
-
 /*
  * Extended attribute SET operations
  */