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authorLinus Torvalds <torvalds@linux-foundation.org>2014-11-02 10:28:43 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2014-11-02 10:28:43 -0800
commit7e05b807b93cc553bc2aa5ae8fac620cece34720 (patch)
tree6240b09f201c210d7e3f5cd46086a64852530de2 /include
parent4cb8c3593bbb884c5c282b1d8502a0930235fe88 (diff)
parent9f2f7d4c8dfcf4617af5de6ea381b91deac3db48 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull VFS fixes from Al Viro: "A bunch of assorted fixes, most of them followups to overlayfs merge" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: ovl: initialize ->is_cursor Return short read or 0 at end of a raw device, not EIO isofs: don't bother with ->d_op for normal case isofs_cmp(): we'll never see a dentry for . or .. overlayfs: fix lockdep misannotation ovl: fix check for cursor overlayfs: barriers for opening upper-layer directory rcu: Provide counterpart to rcu_dereference() for non-RCU situations staging: android: logger: Fix log corruption regression
Diffstat (limited to 'include')
-rw-r--r--include/linux/fs.h10
-rw-r--r--include/linux/rcupdate.h15
2 files changed, 22 insertions, 3 deletions
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 4e41a4a331bb..9ab779e8a63c 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -639,11 +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
{
@@ -651,7 +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*);
@@ -2466,6 +2469,7 @@ 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);
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index a4a819ffb2d1..53ff1a752d7e 100644
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -617,6 +617,21 @@ static inline void rcu_preempt_sleep_check(void)
#define RCU_INITIALIZER(v) (typeof(*(v)) __force __rcu *)(v)
/**
+ * lockless_dereference() - safely load a pointer for later dereference
+ * @p: The pointer to load
+ *
+ * Similar to rcu_dereference(), but for situations where the pointed-to
+ * object's lifetime is managed by something other than RCU. That
+ * "something other" might be reference counting or simple immortality.
+ */
+#define lockless_dereference(p) \
+({ \
+ typeof(p) _________p1 = ACCESS_ONCE(p); \
+ smp_read_barrier_depends(); /* Dependency order vs. p above. */ \
+ (_________p1); \
+})
+
+/**
* rcu_assign_pointer() - assign to RCU-protected pointer
* @p: pointer to assign to
* @v: value to assign (publish)