[PATCH 1/3] fs/locks: Alloc file_lock where practical

[Benjamin Coddington <bcodding@xxxxxxxxxx>]

Use an allocation it where makes sense to do so.

Signed-off-by: Benjamin Coddington <bcodding@xxxxxxxxxx>
---
 fs/locks.c | 83 ++++++++++++++++++++++++++++++++++----------------------------
 1 file changed, 46 insertions(+), 37 deletions(-)

diff --git a/fs/locks.c b/fs/locks.c
index af2031a1fcff..54aeacf8dc46 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1293,36 +1293,39 @@ int locks_mandatory_locked(struct file *file)
 int locks_mandatory_area(struct inode *inode, struct file *filp, loff_t start,
 			 loff_t end, unsigned char type)
 {
-	struct file_lock fl;
+	struct file_lock *fl;
 	int error;
 	bool sleep = false;
 
-	locks_init_lock(&fl);
-	fl.fl_pid = current->tgid;
-	fl.fl_file = filp;
-	fl.fl_flags = FL_POSIX | FL_ACCESS;
+	fl = locks_alloc_lock();
+	if (fl == NULL)
+		return -ENOMEM;
+
+	fl->fl_pid = current->tgid;
+	fl->fl_file = filp;
+	fl->fl_flags = FL_POSIX | FL_ACCESS;
 	if (filp && !(filp->f_flags & O_NONBLOCK))
 		sleep = true;
-	fl.fl_type = type;
-	fl.fl_start = start;
-	fl.fl_end = end;
+	fl->fl_type = type;
+	fl->fl_start = start;
+	fl->fl_end = end;
 
 	for (;;) {
 		if (filp) {
-			fl.fl_owner = filp;
-			fl.fl_flags &= ~FL_SLEEP;
-			error = posix_lock_inode(inode, &fl, NULL);
+			fl->fl_owner = filp;
+			fl->fl_flags &= ~FL_SLEEP;
+			error = posix_lock_inode(inode, fl, NULL);
 			if (!error)
 				break;
 		}
 
 		if (sleep)
-			fl.fl_flags |= FL_SLEEP;
-		fl.fl_owner = current->files;
-		error = posix_lock_inode(inode, &fl, NULL);
+			fl->fl_flags |= FL_SLEEP;
+		fl->fl_owner = current->files;
+		error = posix_lock_inode(inode, fl, NULL);
 		if (error != FILE_LOCK_DEFERRED)
 			break;
-		error = wait_event_interruptible(fl.fl_wait, !fl.fl_next);
+		error = wait_event_interruptible(fl->fl_wait, !fl->fl_next);
 		if (!error) {
 			/*
 			 * If we've been sleeping someone might have
@@ -1332,10 +1335,10 @@ int locks_mandatory_area(struct inode *inode, struct file *filp, loff_t start,
 				continue;
 		}
 
-		locks_delete_block(&fl);
+		locks_delete_block(fl);
 		break;
 	}
-
+	locks_free_lock(fl);
 	return error;
 }
 
@@ -2088,10 +2091,13 @@ static void posix_lock_to_flock64(struct flock64 *flock, struct file_lock *fl)
  */
 int fcntl_getlk(struct file *filp, unsigned int cmd, struct flock __user *l)
 {
-	struct file_lock file_lock;
+	struct file_lock *fl;
 	struct flock flock;
 	int error;
 
+	fl = locks_alloc_lock();
+	if (fl == NULL)
+		return -ENOMEM;
 	error = -EFAULT;
 	if (copy_from_user(&flock, l, sizeof(flock)))
 		goto out;
@@ -2099,7 +2105,7 @@ int fcntl_getlk(struct file *filp, unsigned int cmd, struct flock __user *l)
 	if ((flock.l_type != F_RDLCK) && (flock.l_type != F_WRLCK))
 		goto out;
 
-	error = flock_to_posix_lock(filp, &file_lock, &flock);
+	error = flock_to_posix_lock(filp, fl, &flock);
 	if (error)
 		goto out;
 
@@ -2109,26 +2115,25 @@ int fcntl_getlk(struct file *filp, unsigned int cmd, struct flock __user *l)
 			goto out;
 
 		cmd = F_GETLK;
-		file_lock.fl_flags |= FL_OFDLCK;
-		file_lock.fl_owner = filp;
+		fl->fl_flags |= FL_OFDLCK;
+		fl->fl_owner = filp;
 	}
 
-	error = vfs_test_lock(filp, &file_lock);
+	error = vfs_test_lock(filp, fl);
 	if (error)
 		goto out;
  
-	flock.l_type = file_lock.fl_type;
-	if (file_lock.fl_type != F_UNLCK) {
-		error = posix_lock_to_flock(&flock, &file_lock);
+	flock.l_type = fl->fl_type;
+	if (fl->fl_type != F_UNLCK) {
+		error = posix_lock_to_flock(&flock, fl);
 		if (error)
-			goto rel_priv;
+			goto out;
 	}
 	error = -EFAULT;
 	if (!copy_to_user(l, &flock, sizeof(flock)))
 		error = 0;
-rel_priv:
-	locks_release_private(&file_lock);
 out:
+	locks_free_lock(fl);
 	return error;
 }
 
@@ -2317,10 +2322,14 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd,
  */
 int fcntl_getlk64(struct file *filp, unsigned int cmd, struct flock64 __user *l)
 {
-	struct file_lock file_lock;
+	struct file_lock *fl;
 	struct flock64 flock;
 	int error;
 
+	fl = locks_alloc_lock();
+	if (fl == NULL)
+		return -ENOMEM;
+
 	error = -EFAULT;
 	if (copy_from_user(&flock, l, sizeof(flock)))
 		goto out;
@@ -2328,7 +2337,7 @@ int fcntl_getlk64(struct file *filp, unsigned int cmd, struct flock64 __user *l)
 	if ((flock.l_type != F_RDLCK) && (flock.l_type != F_WRLCK))
 		goto out;
 
-	error = flock64_to_posix_lock(filp, &file_lock, &flock);
+	error = flock64_to_posix_lock(filp, fl, &flock);
 	if (error)
 		goto out;
 
@@ -2338,24 +2347,24 @@ int fcntl_getlk64(struct file *filp, unsigned int cmd, struct flock64 __user *l)
 			goto out;
 
 		cmd = F_GETLK64;
-		file_lock.fl_flags |= FL_OFDLCK;
-		file_lock.fl_owner = filp;
+		fl->fl_flags |= FL_OFDLCK;
+		fl->fl_owner = filp;
 	}
 
-	error = vfs_test_lock(filp, &file_lock);
+	error = vfs_test_lock(filp, fl);
 	if (error)
 		goto out;
 
-	flock.l_type = file_lock.fl_type;
-	if (file_lock.fl_type != F_UNLCK)
-		posix_lock_to_flock64(&flock, &file_lock);
+	flock.l_type = fl->fl_type;
+	if (fl->fl_type != F_UNLCK)
+		posix_lock_to_flock64(&flock, fl);
 
 	error = -EFAULT;
 	if (!copy_to_user(l, &flock, sizeof(flock)))
 		error = 0;
 
-	locks_release_private(&file_lock);
 out:
+	locks_free_lock(fl);
 	return error;
 }
 
-- 
2.9.3