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-rw-r--r--fs/locks.c147
1 files changed, 86 insertions, 61 deletions
diff --git a/fs/locks.c b/fs/locks.c
index 909eab8fb1d..4d9e71d43e7 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -139,13 +139,10 @@ int lease_break_time = 45;
#define for_each_lock(inode, lockp) \
for (lockp = &inode->i_flock; *lockp != NULL; lockp = &(*lockp)->fl_next)
-LIST_HEAD(file_lock_list);
-
-EXPORT_SYMBOL(file_lock_list);
-
+static LIST_HEAD(file_lock_list);
static LIST_HEAD(blocked_list);
-static kmem_cache_t *filelock_cache;
+static kmem_cache_t *filelock_cache __read_mostly;
/* Allocate an empty lock structure. */
static struct file_lock *locks_alloc_lock(void)
@@ -153,6 +150,21 @@ static struct file_lock *locks_alloc_lock(void)
return kmem_cache_alloc(filelock_cache, SLAB_KERNEL);
}
+static void locks_release_private(struct file_lock *fl)
+{
+ if (fl->fl_ops) {
+ if (fl->fl_ops->fl_release_private)
+ fl->fl_ops->fl_release_private(fl);
+ fl->fl_ops = NULL;
+ }
+ if (fl->fl_lmops) {
+ if (fl->fl_lmops->fl_release_private)
+ fl->fl_lmops->fl_release_private(fl);
+ fl->fl_lmops = NULL;
+ }
+
+}
+
/* Free a lock which is not in use. */
static void locks_free_lock(struct file_lock *fl)
{
@@ -169,18 +181,7 @@ static void locks_free_lock(struct file_lock *fl)
if (!list_empty(&fl->fl_link))
panic("Attempting to free lock on active lock list");
- if (fl->fl_ops) {
- if (fl->fl_ops->fl_release_private)
- fl->fl_ops->fl_release_private(fl);
- fl->fl_ops = NULL;
- }
-
- if (fl->fl_lmops) {
- if (fl->fl_lmops->fl_release_private)
- fl->fl_lmops->fl_release_private(fl);
- fl->fl_lmops = NULL;
- }
-
+ locks_release_private(fl);
kmem_cache_free(filelock_cache, fl);
}
@@ -218,24 +219,46 @@ static void init_once(void *foo, kmem_cache_t *cache, unsigned long flags)
locks_init_lock(lock);
}
+static void locks_copy_private(struct file_lock *new, struct file_lock *fl)
+{
+ if (fl->fl_ops) {
+ if (fl->fl_ops->fl_copy_lock)
+ fl->fl_ops->fl_copy_lock(new, fl);
+ new->fl_ops = fl->fl_ops;
+ }
+ if (fl->fl_lmops) {
+ if (fl->fl_lmops->fl_copy_lock)
+ fl->fl_lmops->fl_copy_lock(new, fl);
+ new->fl_lmops = fl->fl_lmops;
+ }
+}
+
/*
* Initialize a new lock from an existing file_lock structure.
*/
-void locks_copy_lock(struct file_lock *new, struct file_lock *fl)
+static void __locks_copy_lock(struct file_lock *new, const struct file_lock *fl)
{
new->fl_owner = fl->fl_owner;
new->fl_pid = fl->fl_pid;
- new->fl_file = fl->fl_file;
+ new->fl_file = NULL;
new->fl_flags = fl->fl_flags;
new->fl_type = fl->fl_type;
new->fl_start = fl->fl_start;
new->fl_end = fl->fl_end;
+ new->fl_ops = NULL;
+ new->fl_lmops = NULL;
+}
+
+void locks_copy_lock(struct file_lock *new, struct file_lock *fl)
+{
+ locks_release_private(new);
+
+ __locks_copy_lock(new, fl);
+ new->fl_file = fl->fl_file;
new->fl_ops = fl->fl_ops;
new->fl_lmops = fl->fl_lmops;
- if (fl->fl_ops && fl->fl_ops->fl_copy_lock)
- fl->fl_ops->fl_copy_lock(new, fl);
- if (fl->fl_lmops && fl->fl_lmops->fl_copy_lock)
- fl->fl_lmops->fl_copy_lock(new, fl);
+
+ locks_copy_private(new, fl);
}
EXPORT_SYMBOL(locks_copy_lock);
@@ -510,12 +533,7 @@ static void locks_delete_block(struct file_lock *waiter)
static void locks_insert_block(struct file_lock *blocker,
struct file_lock *waiter)
{
- if (!list_empty(&waiter->fl_block)) {
- printk(KERN_ERR "locks_insert_block: removing duplicated lock "
- "(pid=%d %Ld-%Ld type=%d)\n", waiter->fl_pid,
- waiter->fl_start, waiter->fl_end, waiter->fl_type);
- __locks_delete_block(waiter);
- }
+ BUG_ON(!list_empty(&waiter->fl_block));
list_add_tail(&waiter->fl_block, &blocker->fl_block);
waiter->fl_next = blocker;
if (IS_POSIX(blocker))
@@ -654,8 +672,9 @@ static int locks_block_on_timeout(struct file_lock *blocker, struct file_lock *w
return result;
}
-struct file_lock *
-posix_test_lock(struct file *filp, struct file_lock *fl)
+int
+posix_test_lock(struct file *filp, struct file_lock *fl,
+ struct file_lock *conflock)
{
struct file_lock *cfl;
@@ -666,9 +685,13 @@ posix_test_lock(struct file *filp, struct file_lock *fl)
if (posix_locks_conflict(cfl, fl))
break;
}
+ if (cfl) {
+ __locks_copy_lock(conflock, cfl);
+ unlock_kernel();
+ return 1;
+ }
unlock_kernel();
-
- return (cfl);
+ return 0;
}
EXPORT_SYMBOL(posix_test_lock);
@@ -769,9 +792,7 @@ out:
return error;
}
-EXPORT_SYMBOL(posix_lock_file);
-
-static int __posix_lock_file(struct inode *inode, struct file_lock *request)
+static int __posix_lock_file_conf(struct inode *inode, struct file_lock *request, struct file_lock *conflock)
{
struct file_lock *fl;
struct file_lock *new_fl, *new_fl2;
@@ -795,6 +816,8 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request)
continue;
if (!posix_locks_conflict(request, fl))
continue;
+ if (conflock)
+ locks_copy_lock(conflock, fl);
error = -EAGAIN;
if (!(request->fl_flags & FL_SLEEP))
goto out;
@@ -904,7 +927,8 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request)
fl->fl_start = request->fl_start;
fl->fl_end = request->fl_end;
fl->fl_type = request->fl_type;
- fl->fl_u = request->fl_u;
+ locks_release_private(fl);
+ locks_copy_private(fl, request);
request = fl;
added = 1;
}
@@ -963,8 +987,24 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request)
*/
int posix_lock_file(struct file *filp, struct file_lock *fl)
{
- return __posix_lock_file(filp->f_dentry->d_inode, fl);
+ return __posix_lock_file_conf(filp->f_dentry->d_inode, fl, NULL);
}
+EXPORT_SYMBOL(posix_lock_file);
+
+/**
+ * posix_lock_file_conf - Apply a POSIX-style lock to a file
+ * @filp: The file to apply the lock to
+ * @fl: The lock to be applied
+ * @conflock: Place to return a copy of the conflicting lock, if found.
+ *
+ * Except for the conflock parameter, acts just like posix_lock_file.
+ */
+int posix_lock_file_conf(struct file *filp, struct file_lock *fl,
+ struct file_lock *conflock)
+{
+ return __posix_lock_file_conf(filp->f_dentry->d_inode, fl, conflock);
+}
+EXPORT_SYMBOL(posix_lock_file_conf);
/**
* posix_lock_file_wait - Apply a POSIX-style lock to a file
@@ -980,7 +1020,7 @@ int posix_lock_file_wait(struct file *filp, struct file_lock *fl)
int error;
might_sleep ();
for (;;) {
- error = __posix_lock_file(filp->f_dentry->d_inode, fl);
+ error = posix_lock_file(filp, fl);
if ((error != -EAGAIN) || !(fl->fl_flags & FL_SLEEP))
break;
error = wait_event_interruptible(fl->fl_wait, !fl->fl_next);
@@ -1052,7 +1092,7 @@ int locks_mandatory_area(int read_write, struct inode *inode,
fl.fl_end = offset + count - 1;
for (;;) {
- error = __posix_lock_file(inode, &fl);
+ error = __posix_lock_file_conf(inode, &fl, NULL);
if (error != -EAGAIN)
break;
if (!(fl.fl_flags & FL_SLEEP))
@@ -1544,7 +1584,7 @@ asmlinkage long sys_flock(unsigned int fd, unsigned int cmd)
*/
int fcntl_getlk(struct file *filp, struct flock __user *l)
{
- struct file_lock *fl, file_lock;
+ struct file_lock *fl, cfl, file_lock;
struct flock flock;
int error;
@@ -1568,7 +1608,7 @@ int fcntl_getlk(struct file *filp, struct flock __user *l)
else
fl = (file_lock.fl_type == F_UNLCK ? NULL : &file_lock);
} else {
- fl = posix_test_lock(filp, &file_lock);
+ fl = (posix_test_lock(filp, &file_lock, &cfl) ? &cfl : NULL);
}
flock.l_type = F_UNLCK;
@@ -1665,7 +1705,7 @@ again:
error = filp->f_op->lock(filp, cmd, file_lock);
else {
for (;;) {
- error = __posix_lock_file(inode, file_lock);
+ error = posix_lock_file(filp, file_lock);
if ((error != -EAGAIN) || (cmd == F_SETLK))
break;
error = wait_event_interruptible(file_lock->fl_wait,
@@ -1698,7 +1738,7 @@ out:
*/
int fcntl_getlk64(struct file *filp, struct flock64 __user *l)
{
- struct file_lock *fl, file_lock;
+ struct file_lock *fl, cfl, file_lock;
struct flock64 flock;
int error;
@@ -1722,7 +1762,7 @@ int fcntl_getlk64(struct file *filp, struct flock64 __user *l)
else
fl = (file_lock.fl_type == F_UNLCK ? NULL : &file_lock);
} else {
- fl = posix_test_lock(filp, &file_lock);
+ fl = (posix_test_lock(filp, &file_lock, &cfl) ? &cfl : NULL);
}
flock.l_type = F_UNLCK;
@@ -1808,7 +1848,7 @@ again:
error = filp->f_op->lock(filp, cmd, file_lock);
else {
for (;;) {
- error = __posix_lock_file(inode, file_lock);
+ error = posix_lock_file(filp, file_lock);
if ((error != -EAGAIN) || (cmd == F_SETLK64))
break;
error = wait_event_interruptible(file_lock->fl_wait,
@@ -1936,21 +1976,6 @@ void locks_remove_flock(struct file *filp)
}
/**
- * posix_block_lock - blocks waiting for a file lock
- * @blocker: the lock which is blocking
- * @waiter: the lock which conflicts and has to wait
- *
- * lockd needs to block waiting for locks.
- */
-void
-posix_block_lock(struct file_lock *blocker, struct file_lock *waiter)
-{
- locks_insert_block(blocker, waiter);
-}
-
-EXPORT_SYMBOL(posix_block_lock);
-
-/**
* posix_unblock_lock - stop waiting for a file lock
* @filp: how the file was opened
* @waiter: the lock which was waiting
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-11-25 17:31:55 +0000