From: "J. Bruce Fields" <bfields@xxxxxxxxxx>
We want to do this elsewhere as well.
Also catch any attempts to use it for directories (where this ordering
would conflict with ancestor-first directory ordering in lock_rename).
Cc: Andreas Dilger <adilger.kernel@xxxxxxxxx>
Cc: Dave Chinner <david@xxxxxxxxxxxxx>
Acked-by: Jeff Layton <jlayton@xxxxxxxxxx>
Acked-by: "Theodore Ts'o" <tytso@xxxxxxx>
Signed-off-by: J. Bruce Fields <bfields@xxxxxxxxxx>
---
fs/ext4/ext4.h | 2 --
fs/ext4/ioctl.c | 4 ++--
fs/ext4/move_extent.c | 40 ++--------------------------------------
fs/inode.c | 36 ++++++++++++++++++++++++++++++++++++
include/linux/fs.h | 3 +++
5 files changed, 43 insertions(+), 42 deletions(-)
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index b577e45..c8fcdfd 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2699,8 +2699,6 @@ extern void ext4_double_down_write_data_sem(struct inode *first,
struct inode *second);
extern void ext4_double_up_write_data_sem(struct inode *orig_inode,
struct inode *donor_inode);
-void ext4_inode_double_lock(struct inode *inode1, struct inode *inode2);
-void ext4_inode_double_unlock(struct inode *inode1, struct inode *inode2);
extern int ext4_move_extents(struct file *o_filp, struct file *d_filp,
__u64 start_orig, __u64 start_donor,
__u64 len, __u64 *moved_len);
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index 9491ac0..12048f7 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -129,7 +129,7 @@ static long swap_inode_boot_loader(struct super_block *sb,
/* Protect orig inodes against a truncate and make sure,
* that only 1 swap_inode_boot_loader is running. */
- ext4_inode_double_lock(inode, inode_bl);
+ lock_two_nondirectories(inode, inode_bl);
truncate_inode_pages(&inode->i_data, 0);
truncate_inode_pages(&inode_bl->i_data, 0);
@@ -204,7 +204,7 @@ static long swap_inode_boot_loader(struct super_block *sb,
ext4_inode_resume_unlocked_dio(inode);
ext4_inode_resume_unlocked_dio(inode_bl);
- ext4_inode_double_unlock(inode, inode_bl);
+ unlock_two_nondirectories(inode, inode_bl);
iput(inode_bl);
diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c
index e86dddb..f591a75 100644
--- a/fs/ext4/move_extent.c
+++ b/fs/ext4/move_extent.c
@@ -1203,42 +1203,6 @@ mext_check_arguments(struct inode *orig_inode,
}
/**
- * ext4_inode_double_lock - Lock i_mutex on both @inode1 and @inode2
- *
- * @inode1: the inode structure
- * @inode2: the inode structure
- *
- * Lock two inodes' i_mutex
- */
-void
-ext4_inode_double_lock(struct inode *inode1, struct inode *inode2)
-{
- BUG_ON(inode1 == inode2);
- if (inode1 < inode2) {
- mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
- mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
- } else {
- mutex_lock_nested(&inode2->i_mutex, I_MUTEX_PARENT);
- mutex_lock_nested(&inode1->i_mutex, I_MUTEX_CHILD);
- }
-}
-
-/**
- * ext4_inode_double_unlock - Release i_mutex on both @inode1 and @inode2
- *
- * @inode1: the inode that is released first
- * @inode2: the inode that is released second
- *
- */
-
-void
-ext4_inode_double_unlock(struct inode *inode1, struct inode *inode2)
-{
- mutex_unlock(&inode1->i_mutex);
- mutex_unlock(&inode2->i_mutex);
-}
-
-/**
* ext4_move_extents - Exchange the specified range of a file
*
* @o_filp: file structure of the original file
@@ -1327,7 +1291,7 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp,
return -EINVAL;
}
/* Protect orig and donor inodes against a truncate */
- ext4_inode_double_lock(orig_inode, donor_inode);
+ lock_two_nondirectories(orig_inode, donor_inode);
/* Wait for all existing dio workers */
ext4_inode_block_unlocked_dio(orig_inode);
@@ -1535,7 +1499,7 @@ out:
ext4_double_up_write_data_sem(orig_inode, donor_inode);
ext4_inode_resume_unlocked_dio(orig_inode);
ext4_inode_resume_unlocked_dio(donor_inode);
- ext4_inode_double_unlock(orig_inode, donor_inode);
+ unlock_two_nondirectories(orig_inode, donor_inode);
return ret;
}
diff --git a/fs/inode.c b/fs/inode.c
index d6dfb09..57d273e 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -982,6 +982,42 @@ void unlock_new_inode(struct inode *inode)
EXPORT_SYMBOL(unlock_new_inode);
/**
+ * lock_two_nondirectories - take two i_mutexes on non-directory objects
+ * @inode1: first inode to lock
+ * @inode2: second inode to lock
+ */
+void lock_two_nondirectories(struct inode *inode1, struct inode *inode2)
+{
+ WARN_ON_ONCE(S_ISDIR(inode1->i_mode));
+ if (inode1 == inode2 || !inode2) {
+ mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
+ return;
+ }
+ WARN_ON_ONCE(S_ISDIR(inode2->i_mode));
+ if (inode1 < inode2) {
+ mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
+ mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
+ } else {
+ mutex_lock_nested(&inode2->i_mutex, I_MUTEX_PARENT);
+ mutex_lock_nested(&inode1->i_mutex, I_MUTEX_CHILD);
+ }
+}
+EXPORT_SYMBOL(lock_two_nondirectories);
+
+/**
+ * unlock_two_nondirectories - release locks from lock_two_nondirectories()
+ * @inode1: first inode to unlock
+ * @inode2: second inode to unlock
+ */
+void unlock_two_nondirectories(struct inode *inode1, struct inode *inode2)
+{
+ mutex_unlock(&inode1->i_mutex);
+ if (inode2 && inode2 != inode1)
+ mutex_unlock(&inode2->i_mutex);
+}
+EXPORT_SYMBOL(unlock_two_nondirectories);
+
+/**
* iget5_locked - obtain an inode from a mounted file system
* @sb: super block of file system
* @hashval: hash value (usually inode number) to get
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 9818747..431427a 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -636,6 +636,9 @@ enum inode_i_mutex_lock_class
I_MUTEX_QUOTA
};
+void lock_two_nondirectories(struct inode *, struct inode*);
+void unlock_two_nondirectories(struct inode *, struct inode*);
+
/*
* NOTE: in a 32bit arch with a preemptable kernel and
* an UP compile the i_size_read/write must be atomic
--
1.7.9.5
--
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