quota: Use function to provide i_dquot pointers

[firefly-linux-kernel-4.4.55.git] / include / linux / fs.h

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 69118b3cb917b447731ab8ff420c57122898cf37..8c093ad4952216485392d1b249df4bef185ebf88 100644 (file)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -261,6 +261,12 @@ struct iattr {
  */
 #include <linux/quota.h>
 
+/*
+ * Maximum number of layers of fs stack.  Needs to be limited to
+ * prevent kernel stack overflow
+ */
+#define FILESYSTEM_MAX_STACK_DEPTH 2
+
 /** 
  * enum positive_aop_returns - aop return codes with specific semantics
  *
@@ -633,11 +639,13 @@ static inline int inode_unhashed(struct inode *inode)
  * 2: child/target
  * 3: xattr
  * 4: second non-directory
- * The last is for certain operations (such as rename) which lock two
+ * 5: second parent (when locking independent directories in rename)
+ *
+ * I_MUTEX_NONDIR2 is for certain operations (such as rename) which lock two
  * non-directories at once.
  *
  * The locking order between these classes is
- * parent -> child -> normal -> xattr -> second non-directory
+ * parent[2] -> child -> grandchild -> normal -> xattr -> second non-directory
  */
 enum inode_i_mutex_lock_class
 {
@@ -645,7 +653,8 @@ enum inode_i_mutex_lock_class
        I_MUTEX_PARENT,
        I_MUTEX_CHILD,
        I_MUTEX_XATTR,
-       I_MUTEX_NONDIR2
+       I_MUTEX_NONDIR2,
+       I_MUTEX_PARENT2,
 };
 
 void lock_two_nondirectories(struct inode *, struct inode*);
@@ -1215,6 +1224,7 @@ struct super_block {
        struct backing_dev_info *s_bdi;
        struct mtd_info         *s_mtd;
        struct hlist_node       s_instances;
+       unsigned int            s_quota_types;  /* Bitmask of supported quota types */
        struct quota_info       s_dquot;        /* Diskquota specific options */
 
        struct sb_writers       s_writers;
@@ -1273,6 +1283,11 @@ struct super_block {
        struct list_lru         s_dentry_lru ____cacheline_aligned_in_smp;
        struct list_lru         s_inode_lru ____cacheline_aligned_in_smp;
        struct rcu_head         rcu;
+
+       /*
+        * Indicates how deep in a filesystem stack this SB is
+        */
+       int s_stack_depth;
 };
 
 extern struct timespec current_fs_time(struct super_block *sb);
@@ -1576,6 +1591,7 @@ struct super_operations {
 #ifdef CONFIG_QUOTA
        ssize_t (*quota_read)(struct super_block *, int, char *, size_t, loff_t);
        ssize_t (*quota_write)(struct super_block *, int, const char *, size_t, loff_t);
+       struct dquot **(*get_dquots)(struct inode *);
 #endif
        int (*bdev_try_to_free_page)(struct super_block*, struct page*, gfp_t);
        long (*nr_cached_objects)(struct super_block *, int);
@@ -2455,6 +2471,7 @@ extern ssize_t new_sync_read(struct file *filp, char __user *buf, size_t len, lo
 extern ssize_t new_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);
 
 /* fs/block_dev.c */
+extern ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to);
 extern ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from);
 extern int blkdev_fsync(struct file *filp, loff_t start, loff_t end,
                        int datasync);