Btrfs: finish read pages in the order they are submitted
[linux-2.6.git] / fs / locks.c
index 600d1fb..a8794f2 100644 (file)
 
 #include <linux/capability.h>
 #include <linux/file.h>
+#include <linux/fdtable.h>
 #include <linux/fs.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/syscalls.h>
 #include <linux/time.h>
 #include <linux/rcupdate.h>
+#include <linux/pid_namespace.h>
 
-#include <asm/semaphore.h>
 #include <asm/uaccess.h>
 
 #define IS_POSIX(fl)   (fl->fl_flags & FL_POSIX)
@@ -139,48 +140,41 @@ 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 struct kmem_cache *filelock_cache __read_mostly;
 
 /* Allocate an empty lock structure. */
 static struct file_lock *locks_alloc_lock(void)
 {
-       return kmem_cache_alloc(filelock_cache, SLAB_KERNEL);
+       return kmem_cache_alloc(filelock_cache, GFP_KERNEL);
 }
 
-/* Free a lock which is not in use. */
-static inline void locks_free_lock(struct file_lock *fl)
+void locks_release_private(struct file_lock *fl)
 {
-       if (fl == NULL) {
-               BUG();
-               return;
-       }
-       if (waitqueue_active(&fl->fl_wait))
-               panic("Attempting to free lock with active wait queue");
-
-       if (!list_empty(&fl->fl_block))
-               panic("Attempting to free lock with active block list");
-
-       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;
        }
 
+}
+EXPORT_SYMBOL_GPL(locks_release_private);
+
+/* Free a lock which is not in use. */
+static void locks_free_lock(struct file_lock *fl)
+{
+       BUG_ON(waitqueue_active(&fl->fl_wait));
+       BUG_ON(!list_empty(&fl->fl_block));
+       BUG_ON(!list_empty(&fl->fl_link));
+
+       locks_release_private(fl);
        kmem_cache_free(filelock_cache, fl);
 }
 
@@ -193,6 +187,7 @@ void locks_init_lock(struct file_lock *fl)
        fl->fl_fasync = NULL;
        fl->fl_owner = NULL;
        fl->fl_pid = 0;
+       fl->fl_nspid = NULL;
        fl->fl_file = NULL;
        fl->fl_flags = 0;
        fl->fl_type = 0;
@@ -207,35 +202,54 @@ EXPORT_SYMBOL(locks_init_lock);
  * Initialises the fields of the file lock which are invariant for
  * free file_locks.
  */
-static void init_once(void *foo, kmem_cache_t *cache, unsigned long flags)
+static void init_once(void *foo)
 {
        struct file_lock *lock = (struct file_lock *) foo;
 
-       if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) !=
-                                       SLAB_CTOR_CONSTRUCTOR)
-               return;
-
        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)
+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;
+}
+EXPORT_SYMBOL(__locks_copy_lock);
+
+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);
@@ -300,14 +314,14 @@ static int flock_to_posix_lock(struct file *filp, struct file_lock *fl,
        off_t start, end;
 
        switch (l->l_whence) {
-       case 0: /*SEEK_SET*/
+       case SEEK_SET:
                start = 0;
                break;
-       case 1: /*SEEK_CUR*/
+       case SEEK_CUR:
                start = filp->f_pos;
                break;
-       case 2: /*SEEK_END*/
-               start = i_size_read(filp->f_dentry->d_inode);
+       case SEEK_END:
+               start = i_size_read(filp->f_path.dentry->d_inode);
                break;
        default:
                return -EINVAL;
@@ -350,14 +364,14 @@ static int flock64_to_posix_lock(struct file *filp, struct file_lock *fl,
        loff_t start;
 
        switch (l->l_whence) {
-       case 0: /*SEEK_SET*/
+       case SEEK_SET:
                start = 0;
                break;
-       case 1: /*SEEK_CUR*/
+       case SEEK_CUR:
                start = filp->f_pos;
                break;
-       case 2: /*SEEK_END*/
-               start = i_size_read(filp->f_dentry->d_inode);
+       case SEEK_END:
+               start = i_size_read(filp->f_path.dentry->d_inode);
                break;
        default:
                return -EINVAL;
@@ -420,7 +434,7 @@ static int lease_mylease_callback(struct file_lock *fl, struct file_lock *try)
        return fl->fl_file == try->fl_file;
 }
 
-static struct lock_manager_operations lease_manager_ops = {
+static const struct lock_manager_operations lease_manager_ops = {
        .fl_break = lease_break_callback,
        .fl_release_private = lease_release_private_callback,
        .fl_mylease = lease_mylease_callback,
@@ -432,15 +446,14 @@ static struct lock_manager_operations lease_manager_ops = {
  */
 static int lease_init(struct file *filp, int type, struct file_lock *fl)
  {
+       if (assign_type(fl, type) != 0)
+               return -EINVAL;
+
        fl->fl_owner = current->files;
        fl->fl_pid = current->tgid;
 
        fl->fl_file = filp;
        fl->fl_flags = FL_LEASE;
-       if (assign_type(fl, type) != 0) {
-               locks_free_lock(fl);
-               return -EINVAL;
-       }
        fl->fl_start = 0;
        fl->fl_end = OFFSET_MAX;
        fl->fl_ops = NULL;
@@ -449,19 +462,20 @@ static int lease_init(struct file *filp, int type, struct file_lock *fl)
 }
 
 /* Allocate a file_lock initialised to this type of lease */
-static int lease_alloc(struct file *filp, int type, struct file_lock **flp)
+static struct file_lock *lease_alloc(struct file *filp, int type)
 {
        struct file_lock *fl = locks_alloc_lock();
-       int error;
+       int error = -ENOMEM;
 
        if (fl == NULL)
-               return -ENOMEM;
+               return ERR_PTR(error);
 
        error = lease_init(filp, type, fl);
-       if (error)
-               return error;
-       *flp = fl;
-       return 0;
+       if (error) {
+               locks_free_lock(fl);
+               return ERR_PTR(error);
+       }
+       return fl;
 }
 
 /* Check if two locks overlap each other.
@@ -475,8 +489,7 @@ static inline int locks_overlap(struct file_lock *fl1, struct file_lock *fl2)
 /*
  * Check whether two locks have the same owner.
  */
-static inline int
-posix_same_owner(struct file_lock *fl1, struct file_lock *fl2)
+static int posix_same_owner(struct file_lock *fl1, struct file_lock *fl2)
 {
        if (fl1->fl_lmops && fl1->fl_lmops->fl_compare_owner)
                return fl2->fl_lmops == fl1->fl_lmops &&
@@ -487,7 +500,7 @@ posix_same_owner(struct file_lock *fl1, struct file_lock *fl2)
 /* Remove waiter from blocker's block list.
  * When blocker ends up pointing to itself then the list is empty.
  */
-static inline void __locks_delete_block(struct file_lock *waiter)
+static void __locks_delete_block(struct file_lock *waiter)
 {
        list_del_init(&waiter->fl_block);
        list_del_init(&waiter->fl_link);
@@ -511,12 +524,7 @@ 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))
@@ -530,7 +538,9 @@ static void locks_insert_block(struct file_lock *blocker,
 static void locks_wake_up_blocks(struct file_lock *blocker)
 {
        while (!list_empty(&blocker->fl_block)) {
-               struct file_lock *waiter = list_entry(blocker->fl_block.next,
+               struct file_lock *waiter;
+
+               waiter = list_first_entry(&blocker->fl_block,
                                struct file_lock, fl_block);
                __locks_delete_block(waiter);
                if (waiter->fl_lmops && waiter->fl_lmops->fl_notify)
@@ -547,12 +557,11 @@ static void locks_insert_lock(struct file_lock **pos, struct file_lock *fl)
 {
        list_add(&fl->fl_link, &file_lock_list);
 
+       fl->fl_nspid = get_pid(task_tgid(current));
+
        /* insert into file's list */
        fl->fl_next = *pos;
        *pos = fl;
-
-       if (fl->fl_ops && fl->fl_ops->fl_insert)
-               fl->fl_ops->fl_insert(fl);
 }
 
 /*
@@ -575,8 +584,10 @@ static void locks_delete_lock(struct file_lock **thisfl_p)
                fl->fl_fasync = NULL;
        }
 
-       if (fl->fl_ops && fl->fl_ops->fl_remove)
-               fl->fl_ops->fl_remove(fl);
+       if (fl->fl_nspid) {
+               put_pid(fl->fl_nspid);
+               fl->fl_nspid = NULL;
+       }
 
        locks_wake_up_blocks(fl);
        locks_free_lock(fl);
@@ -628,99 +639,109 @@ static int flock_locks_conflict(struct file_lock *caller_fl, struct file_lock *s
        return (locks_conflict(caller_fl, sys_fl));
 }
 
-static int interruptible_sleep_on_locked(wait_queue_head_t *fl_wait, int timeout)
-{
-       int result = 0;
-       DECLARE_WAITQUEUE(wait, current);
-
-       __set_current_state(TASK_INTERRUPTIBLE);
-       add_wait_queue(fl_wait, &wait);
-       if (timeout == 0)
-               schedule();
-       else
-               result = schedule_timeout(timeout);
-       if (signal_pending(current))
-               result = -ERESTARTSYS;
-       remove_wait_queue(fl_wait, &wait);
-       __set_current_state(TASK_RUNNING);
-       return result;
-}
-
-static int locks_block_on_timeout(struct file_lock *blocker, struct file_lock *waiter, int time)
-{
-       int result;
-       locks_insert_block(blocker, waiter);
-       result = interruptible_sleep_on_locked(&waiter->fl_wait, time);
-       __locks_delete_block(waiter);
-       return result;
-}
-
-struct file_lock *
+void
 posix_test_lock(struct file *filp, struct file_lock *fl)
 {
        struct file_lock *cfl;
 
        lock_kernel();
-       for (cfl = filp->f_dentry->d_inode->i_flock; cfl; cfl = cfl->fl_next) {
+       for (cfl = filp->f_path.dentry->d_inode->i_flock; cfl; cfl = cfl->fl_next) {
                if (!IS_POSIX(cfl))
                        continue;
-               if (posix_locks_conflict(cfl, fl))
+               if (posix_locks_conflict(fl, cfl))
                        break;
        }
+       if (cfl) {
+               __locks_copy_lock(fl, cfl);
+               if (cfl->fl_nspid)
+                       fl->fl_pid = pid_vnr(cfl->fl_nspid);
+       } else
+               fl->fl_type = F_UNLCK;
        unlock_kernel();
-
-       return (cfl);
+       return;
 }
-
 EXPORT_SYMBOL(posix_test_lock);
 
-/* This function tests for deadlock condition before putting a process to
- * sleep. The detection scheme is no longer recursive. Recursive was neat,
- * but dangerous - we risked stack corruption if the lock data was bad, or
- * if the recursion was too deep for any other reason.
+/*
+ * Deadlock detection:
  *
- * We rely on the fact that a task can only be on one lock's wait queue
- * at a time. When we find blocked_task on a wait queue we can re-search
- * with blocked_task equal to that queue's owner, until either blocked_task
- * isn't found, or blocked_task is found on a queue owned by my_task.
+ * We attempt to detect deadlocks that are due purely to posix file
+ * locks.
  *
- * Note: the above assumption may not be true when handling lock requests
- * from a broken NFS client. But broken NFS clients have a lot more to
- * worry about than proper deadlock detection anyway... --okir
+ * We assume that a task can be waiting for at most one lock at a time.
+ * So for any acquired lock, the process holding that lock may be
+ * waiting on at most one other lock.  That lock in turns may be held by
+ * someone waiting for at most one other lock.  Given a requested lock
+ * caller_fl which is about to wait for a conflicting lock block_fl, we
+ * follow this chain of waiters to ensure we are not about to create a
+ * cycle.
+ *
+ * Since we do this before we ever put a process to sleep on a lock, we
+ * are ensured that there is never a cycle; that is what guarantees that
+ * the while() loop in posix_locks_deadlock() eventually completes.
+ *
+ * Note: the above assumption may not be true when handling lock
+ * requests from a broken NFS client. It may also fail in the presence
+ * of tasks (such as posix threads) sharing the same open file table.
+ *
+ * To handle those cases, we just bail out after a few iterations.
  */
-int posix_locks_deadlock(struct file_lock *caller_fl,
+
+#define MAX_DEADLK_ITERATIONS 10
+
+/* Find a lock that the owner of the given block_fl is blocking on. */
+static struct file_lock *what_owner_is_waiting_for(struct file_lock *block_fl)
+{
+       struct file_lock *fl;
+
+       list_for_each_entry(fl, &blocked_list, fl_link) {
+               if (posix_same_owner(fl, block_fl))
+                       return fl->fl_next;
+       }
+       return NULL;
+}
+
+static int posix_locks_deadlock(struct file_lock *caller_fl,
                                struct file_lock *block_fl)
 {
-       struct list_head *tmp;
+       int i = 0;
 
-next_task:
-       if (posix_same_owner(caller_fl, block_fl))
-               return 1;
-       list_for_each(tmp, &blocked_list) {
-               struct file_lock *fl = list_entry(tmp, struct file_lock, fl_link);
-               if (posix_same_owner(fl, block_fl)) {
-                       fl = fl->fl_next;
-                       block_fl = fl;
-                       goto next_task;
-               }
+       while ((block_fl = what_owner_is_waiting_for(block_fl))) {
+               if (i++ > MAX_DEADLK_ITERATIONS)
+                       return 0;
+               if (posix_same_owner(caller_fl, block_fl))
+                       return 1;
        }
        return 0;
 }
 
-EXPORT_SYMBOL(posix_locks_deadlock);
-
 /* Try to create a FLOCK lock on filp. We always insert new FLOCK locks
- * at the head of the list, but that's secret knowledge known only to
- * flock_lock_file and posix_lock_file.
+ * after any leases, but before any posix locks.
+ *
+ * Note that if called with an FL_EXISTS argument, the caller may determine
+ * whether or not a lock was successfully freed by testing the return
+ * value for -ENOENT.
  */
-static int flock_lock_file(struct file *filp, struct file_lock *new_fl)
+static int flock_lock_file(struct file *filp, struct file_lock *request)
 {
+       struct file_lock *new_fl = NULL;
        struct file_lock **before;
-       struct inode * inode = filp->f_dentry->d_inode;
+       struct inode * inode = filp->f_path.dentry->d_inode;
        int error = 0;
        int found = 0;
 
        lock_kernel();
+       if (request->fl_flags & FL_ACCESS)
+               goto find_conflict;
+
+       if (request->fl_type != F_UNLCK) {
+               error = -ENOMEM;
+               new_fl = locks_alloc_lock();
+               if (new_fl == NULL)
+                       goto out;
+               error = 0;
+       }
+
        for_each_lock(inode, before) {
                struct file_lock *fl = *before;
                if (IS_POSIX(fl))
@@ -729,16 +750,18 @@ static int flock_lock_file(struct file *filp, struct file_lock *new_fl)
                        continue;
                if (filp != fl->fl_file)
                        continue;
-               if (new_fl->fl_type == fl->fl_type)
+               if (request->fl_type == fl->fl_type)
                        goto out;
                found = 1;
                locks_delete_lock(before);
                break;
        }
-       unlock_kernel();
 
-       if (new_fl->fl_type == F_UNLCK)
-               return 0;
+       if (request->fl_type == F_UNLCK) {
+               if ((request->fl_flags & FL_EXISTS) && !found)
+                       error = -ENOENT;
+               goto out;
+       }
 
        /*
         * If a higher-priority process was blocked on the old file lock,
@@ -747,35 +770,41 @@ static int flock_lock_file(struct file *filp, struct file_lock *new_fl)
        if (found)
                cond_resched();
 
-       lock_kernel();
+find_conflict:
        for_each_lock(inode, before) {
                struct file_lock *fl = *before;
                if (IS_POSIX(fl))
                        break;
                if (IS_LEASE(fl))
                        continue;
-               if (!flock_locks_conflict(new_fl, fl))
+               if (!flock_locks_conflict(request, fl))
                        continue;
                error = -EAGAIN;
-               if (new_fl->fl_flags & FL_SLEEP) {
-                       locks_insert_block(fl, new_fl);
-               }
+               if (!(request->fl_flags & FL_SLEEP))
+                       goto out;
+               error = FILE_LOCK_DEFERRED;
+               locks_insert_block(fl, request);
                goto out;
        }
-       locks_insert_lock(&inode->i_flock, new_fl);
+       if (request->fl_flags & FL_ACCESS)
+               goto out;
+       locks_copy_lock(new_fl, request);
+       locks_insert_lock(before, new_fl);
+       new_fl = NULL;
        error = 0;
 
 out:
        unlock_kernel();
+       if (new_fl)
+               locks_free_lock(new_fl);
        return error;
 }
 
-EXPORT_SYMBOL(posix_lock_file);
-
-static int __posix_lock_file(struct inode *inode, struct file_lock *request)
+static int __posix_lock_file(struct inode *inode, struct file_lock *request, struct file_lock *conflock)
 {
        struct file_lock *fl;
-       struct file_lock *new_fl, *new_fl2;
+       struct file_lock *new_fl = NULL;
+       struct file_lock *new_fl2 = NULL;
        struct file_lock *left = NULL;
        struct file_lock *right = NULL;
        struct file_lock **before;
@@ -784,25 +813,33 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request)
        /*
         * We may need two file_lock structures for this operation,
         * so we get them in advance to avoid races.
+        *
+        * In some cases we can be sure, that no new locks will be needed
         */
-       new_fl = locks_alloc_lock();
-       new_fl2 = locks_alloc_lock();
+       if (!(request->fl_flags & FL_ACCESS) &&
+           (request->fl_type != F_UNLCK ||
+            request->fl_start != 0 || request->fl_end != OFFSET_MAX)) {
+               new_fl = locks_alloc_lock();
+               new_fl2 = locks_alloc_lock();
+       }
 
        lock_kernel();
        if (request->fl_type != F_UNLCK) {
                for_each_lock(inode, before) {
-                       struct file_lock *fl = *before;
+                       fl = *before;
                        if (!IS_POSIX(fl))
                                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;
                        error = -EDEADLK;
                        if (posix_locks_deadlock(request, fl))
                                goto out;
-                       error = -EAGAIN;
+                       error = FILE_LOCK_DEFERRED;
                        locks_insert_block(fl, request);
                        goto out;
                }
@@ -813,14 +850,7 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request)
        if (request->fl_flags & FL_ACCESS)
                goto out;
 
-       error = -ENOLCK; /* "no luck" */
-       if (!(new_fl && new_fl2))
-               goto out;
-
        /*
-        * We've allocated the new locks in advance, so there are no
-        * errors possible (and no blocking operations) from here on.
-        * 
         * Find the first old lock with the same owner as the new lock.
         */
        
@@ -905,7 +935,8 @@ 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;
                        }
@@ -916,10 +947,28 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request)
                before = &fl->fl_next;
        }
 
+       /*
+        * The above code only modifies existing locks in case of
+        * merging or replacing.  If new lock(s) need to be inserted
+        * all modifications are done bellow this, so it's safe yet to
+        * bail out.
+        */
+       error = -ENOLCK; /* "no luck" */
+       if (right && left == right && !new_fl2)
+               goto out;
+
        error = 0;
        if (!added) {
-               if (request->fl_type == F_UNLCK)
+               if (request->fl_type == F_UNLCK) {
+                       if (request->fl_flags & FL_EXISTS)
+                               error = -ENOENT;
+                       goto out;
+               }
+
+               if (!new_fl) {
+                       error = -ENOLCK;
                        goto out;
+               }
                locks_copy_lock(new_fl, request);
                locks_insert_lock(before, new_fl);
                new_fl = NULL;
@@ -957,15 +1006,22 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request)
  * posix_lock_file - 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.
  *
  * Add a POSIX style lock to a file.
  * We merge adjacent & overlapping locks whenever possible.
  * POSIX locks are sorted by owner task, then by starting address
+ *
+ * Note that if called with an FL_EXISTS argument, the caller may determine
+ * whether or not a lock was successfully freed by testing the return
+ * value for -ENOENT.
  */
-int posix_lock_file(struct file *filp, struct file_lock *fl)
+int posix_lock_file(struct file *filp, struct file_lock *fl,
+                       struct file_lock *conflock)
 {
-       return __posix_lock_file(filp->f_dentry->d_inode, fl);
+       return __posix_lock_file(filp->f_path.dentry->d_inode, fl, conflock);
 }
+EXPORT_SYMBOL(posix_lock_file);
 
 /**
  * posix_lock_file_wait - Apply a POSIX-style lock to a file
@@ -981,8 +1037,8 @@ 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);
-               if ((error != -EAGAIN) || !(fl->fl_flags & FL_SLEEP))
+               error = posix_lock_file(filp, fl, NULL);
+               if (error != FILE_LOCK_DEFERRED)
                        break;
                error = wait_event_interruptible(fl->fl_wait, !fl->fl_next);
                if (!error)
@@ -1053,10 +1109,8 @@ int locks_mandatory_area(int read_write, struct inode *inode,
        fl.fl_end = offset + count - 1;
 
        for (;;) {
-               error = __posix_lock_file(inode, &fl);
-               if (error != -EAGAIN)
-                       break;
-               if (!(fl.fl_flags & FL_SLEEP))
+               error = __posix_lock_file(inode, &fl, NULL);
+               if (error != FILE_LOCK_DEFERRED)
                        break;
                error = wait_event_interruptible(fl.fl_wait, !fl.fl_next);
                if (!error) {
@@ -1064,7 +1118,7 @@ int locks_mandatory_area(int read_write, struct inode *inode,
                         * If we've been sleeping someone might have
                         * changed the permissions behind our back.
                         */
-                       if ((inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
+                       if (__mandatory_lock(inode))
                                continue;
                }
 
@@ -1105,7 +1159,6 @@ static void time_out_leases(struct inode *inode)
                        before = &fl->fl_next;
                        continue;
                }
-               printk(KERN_INFO "lease broken - owner pid = %d\n", fl->fl_pid);
                lease_modify(before, fl->fl_type & ~F_INPROGRESS);
                if (fl == *before)      /* lease_modify may have freed fl */
                        before = &fl->fl_next;
@@ -1117,9 +1170,9 @@ static void time_out_leases(struct inode *inode)
  *     @inode: the inode of the file to return
  *     @mode: the open mode (read or write)
  *
- *     break_lease (inlined for speed) has checked there already
- *     is a lease on this file.  Leases are broken on a call to open()
- *     or truncate().  This function can sleep unless you
+ *     break_lease (inlined for speed) has checked there already is at least
+ *     some kind of lock (maybe a lease) on this file.  Leases are broken on
+ *     a call to open() or truncate().  This function can sleep unless you
  *     specified %O_NONBLOCK to your open().
  */
 int __break_lease(struct inode *inode, unsigned int mode)
@@ -1127,12 +1180,10 @@ int __break_lease(struct inode *inode, unsigned int mode)
        int error = 0, future;
        struct file_lock *new_fl, *flock;
        struct file_lock *fl;
-       int alloc_err;
        unsigned long break_time;
        int i_have_this_lease = 0;
 
-       alloc_err = lease_alloc(NULL, mode & FMODE_WRITE ? F_WRLCK : F_RDLCK,
-                       &new_fl);
+       new_fl = lease_alloc(NULL, mode & FMODE_WRITE ? F_WRLCK : F_RDLCK);
 
        lock_kernel();
 
@@ -1160,8 +1211,9 @@ int __break_lease(struct inode *inode, unsigned int mode)
                goto out;
        }
 
-       if (alloc_err && !i_have_this_lease && ((mode & O_NONBLOCK) == 0)) {
-               error = alloc_err;
+       if (IS_ERR(new_fl) && !i_have_this_lease
+                       && ((mode & O_NONBLOCK) == 0)) {
+               error = PTR_ERR(new_fl);
                goto out;
        }
 
@@ -1193,7 +1245,10 @@ restart:
                if (break_time == 0)
                        break_time++;
        }
-       error = locks_block_on_timeout(flock, new_fl, break_time);
+       locks_insert_block(flock, new_fl);
+       error = wait_event_interruptible_timeout(new_fl->fl_wait,
+                                               !new_fl->fl_next, break_time);
+       __locks_delete_block(new_fl);
        if (error >= 0) {
                if (error == 0)
                        time_out_leases(inode);
@@ -1208,7 +1263,7 @@ restart:
 
 out:
        unlock_kernel();
-       if (!alloc_err)
+       if (!IS_ERR(new_fl))
                locks_free_lock(new_fl);
        return error;
 }
@@ -1216,13 +1271,13 @@ out:
 EXPORT_SYMBOL(__break_lease);
 
 /**
- *     lease_get_mtime
+ *     lease_get_mtime - get the last modified time of an inode
  *     @inode: the inode
  *      @time:  pointer to a timespec which will contain the last modified time
  *
  * This is to force NFS clients to flush their caches for files with
  * exclusive leases.  The justification is that if someone has an
- * exclusive lease, then they could be modifiying it.
+ * exclusive lease, then they could be modifying it.
  */
 void lease_get_mtime(struct inode *inode, struct timespec *time)
 {
@@ -1264,8 +1319,8 @@ int fcntl_getlease(struct file *filp)
        int type = F_UNLCK;
 
        lock_kernel();
-       time_out_leases(filp->f_dentry->d_inode);
-       for (fl = filp->f_dentry->d_inode->i_flock; fl && IS_LEASE(fl);
+       time_out_leases(filp->f_path.dentry->d_inode);
+       for (fl = filp->f_path.dentry->d_inode->i_flock; fl && IS_LEASE(fl);
                        fl = fl->fl_next) {
                if (fl->fl_file == filp) {
                        type = fl->fl_type & ~F_INPROGRESS;
@@ -1277,7 +1332,7 @@ int fcntl_getlease(struct file *filp)
 }
 
 /**
- *     __setlease      -       sets a lease on an open file
+ *     generic_setlease        -       sets a lease on an open file
  *     @filp: file pointer
  *     @arg: type of lease to obtain
  *     @flp: input - file_lock to use, output - file_lock inserted
@@ -1287,28 +1342,42 @@ int fcntl_getlease(struct file *filp)
  *
  *     Called with kernel lock held.
  */
-static int __setlease(struct file *filp, long arg, struct file_lock **flp)
+int generic_setlease(struct file *filp, long arg, struct file_lock **flp)
 {
        struct file_lock *fl, **before, **my_before = NULL, *lease;
-       struct dentry *dentry = filp->f_dentry;
+       struct file_lock *new_fl = NULL;
+       struct dentry *dentry = filp->f_path.dentry;
        struct inode *inode = dentry->d_inode;
        int error, rdlease_count = 0, wrlease_count = 0;
 
+       if ((current_fsuid() != inode->i_uid) && !capable(CAP_LEASE))
+               return -EACCES;
+       if (!S_ISREG(inode->i_mode))
+               return -EINVAL;
+       error = security_file_lock(filp, arg);
+       if (error)
+               return error;
+
        time_out_leases(inode);
 
-       error = -EINVAL;
-       if (!flp || !(*flp) || !(*flp)->fl_lmops || !(*flp)->fl_lmops->fl_break)
-               goto out;
+       BUG_ON(!(*flp)->fl_lmops->fl_break);
 
        lease = *flp;
 
-       error = -EAGAIN;
-       if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0))
-               goto out;
-       if ((arg == F_WRLCK)
-           && ((atomic_read(&dentry->d_count) > 1)
-               || (atomic_read(&inode->i_count) > 1)))
-               goto out;
+       if (arg != F_UNLCK) {
+               error = -ENOMEM;
+               new_fl = locks_alloc_lock();
+               if (new_fl == NULL)
+                       goto out;
+
+               error = -EAGAIN;
+               if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0))
+                       goto out;
+               if ((arg == F_WRLCK)
+                   && ((atomic_read(&dentry->d_count) > 1)
+                       || (atomic_read(&inode->i_count) > 1)))
+                       goto out;
+       }
 
        /*
         * At this point, we know that if there is an exclusive
@@ -1334,11 +1403,13 @@ static int __setlease(struct file *filp, long arg, struct file_lock **flp)
                        rdlease_count++;
        }
 
+       error = -EAGAIN;
        if ((arg == F_RDLCK && (wrlease_count > 0)) ||
            (arg == F_WRLCK && ((rdlease_count + wrlease_count) > 0)))
                goto out;
 
        if (my_before != NULL) {
+               *flp = *my_before;
                error = lease->fl_lmops->fl_change(my_before, arg);
                goto out;
        }
@@ -1351,51 +1422,60 @@ static int __setlease(struct file *filp, long arg, struct file_lock **flp)
        if (!leases_enable)
                goto out;
 
-       error = lease_alloc(filp, arg, &fl);
-       if (error)
-               goto out;
-
-       locks_copy_lock(fl, lease);
+       locks_copy_lock(new_fl, lease);
+       locks_insert_lock(before, new_fl);
 
-       locks_insert_lock(before, fl);
+       *flp = new_fl;
+       return 0;
 
-       *flp = fl;
 out:
+       if (new_fl != NULL)
+               locks_free_lock(new_fl);
        return error;
 }
+EXPORT_SYMBOL(generic_setlease);
 
  /**
- *     setlease        -       sets a lease on an open file
+ *     vfs_setlease        -       sets a lease on an open file
  *     @filp: file pointer
  *     @arg: type of lease to obtain
  *     @lease: file_lock to use
  *
  *     Call this to establish a lease on the file.
- *     The fl_lmops fl_break function is required by break_lease
+ *     The (*lease)->fl_lmops->fl_break operation must be set; if not,
+ *     break_lease will oops!
+ *
+ *     This will call the filesystem's setlease file method, if
+ *     defined.  Note that there is no getlease method; instead, the
+ *     filesystem setlease method should call back to setlease() to
+ *     add a lease to the inode's lease list, where fcntl_getlease() can
+ *     find it.  Since fcntl_getlease() only reports whether the current
+ *     task holds a lease, a cluster filesystem need only do this for
+ *     leases held by processes on this node.
+ *
+ *     There is also no break_lease method; filesystems that
+ *     handle their own leases shoud break leases themselves from the
+ *     filesystem's open, create, and (on truncate) setattr methods.
+ *
+ *     Warning: the only current setlease methods exist only to disable
+ *     leases in certain cases.  More vfs changes may be required to
+ *     allow a full filesystem lease implementation.
  */
 
-int setlease(struct file *filp, long arg, struct file_lock **lease)
+int vfs_setlease(struct file *filp, long arg, struct file_lock **lease)
 {
-       struct dentry *dentry = filp->f_dentry;
-       struct inode *inode = dentry->d_inode;
        int error;
 
-       if ((current->fsuid != inode->i_uid) && !capable(CAP_LEASE))
-               return -EACCES;
-       if (!S_ISREG(inode->i_mode))
-               return -EINVAL;
-       error = security_file_lock(filp, arg);
-       if (error)
-               return error;
-
        lock_kernel();
-       error = __setlease(filp, arg, lease);
+       if (filp->f_op && filp->f_op->setlease)
+               error = filp->f_op->setlease(filp, arg, lease);
+       else
+               error = generic_setlease(filp, arg, lease);
        unlock_kernel();
 
        return error;
 }
-
-EXPORT_SYMBOL(setlease);
+EXPORT_SYMBOL_GPL(vfs_setlease);
 
 /**
  *     fcntl_setlease  -       sets a lease on an open file
@@ -1410,18 +1490,9 @@ EXPORT_SYMBOL(setlease);
 int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
 {
        struct file_lock fl, *flp = &fl;
-       struct dentry *dentry = filp->f_dentry;
-       struct inode *inode = dentry->d_inode;
+       struct inode *inode = filp->f_path.dentry->d_inode;
        int error;
 
-       if ((current->fsuid != inode->i_uid) && !capable(CAP_LEASE))
-               return -EACCES;
-       if (!S_ISREG(inode->i_mode))
-               return -EINVAL;
-       error = security_file_lock(filp, arg);
-       if (error)
-               return error;
-
        locks_init_lock(&fl);
        error = lease_init(filp, arg, &fl);
        if (error)
@@ -1429,20 +1500,20 @@ int fcntl_setlease(unsigned int fd, struct file *filp, long arg)
 
        lock_kernel();
 
-       error = __setlease(filp, arg, &flp);
+       error = vfs_setlease(filp, arg, &flp);
        if (error || arg == F_UNLCK)
                goto out_unlock;
 
        error = fasync_helper(fd, filp, 1, &flp->fl_fasync);
        if (error < 0) {
-               /* remove lease just inserted by __setlease */
+               /* remove lease just inserted by setlease */
                flp->fl_type = F_UNLCK | F_INPROGRESS;
-               flp->fl_break_time = jiffies- 10;
+               flp->fl_break_time = jiffies - 10;
                time_out_leases(inode);
                goto out_unlock;
        }
 
-       error = f_setown(filp, current->pid, 0);
+       error = __f_setown(filp, task_pid(current), PIDTYPE_PID, 0);
 out_unlock:
        unlock_kernel();
        return error;
@@ -1461,7 +1532,7 @@ int flock_lock_file_wait(struct file *filp, struct file_lock *fl)
        might_sleep();
        for (;;) {
                error = flock_lock_file(filp, fl);
-               if ((error != -EAGAIN) || !(fl->fl_flags & FL_SLEEP))
+               if (error != FILE_LOCK_DEFERRED)
                        break;
                error = wait_event_interruptible(fl->fl_wait, !fl->fl_next);
                if (!error)
@@ -1494,7 +1565,7 @@ EXPORT_SYMBOL(flock_lock_file_wait);
  *     %LOCK_MAND can be combined with %LOCK_READ or %LOCK_WRITE to allow other
  *     processes read and write access respectively.
  */
-asmlinkage long sys_flock(unsigned int fd, unsigned int cmd)
+SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd)
 {
        struct file *filp;
        struct file_lock *lock;
@@ -1510,7 +1581,8 @@ asmlinkage long sys_flock(unsigned int fd, unsigned int cmd)
        cmd &= ~LOCK_NB;
        unlock = (cmd == LOCK_UN);
 
-       if (!unlock && !(cmd & LOCK_MAND) && !(filp->f_mode & 3))
+       if (!unlock && !(cmd & LOCK_MAND) &&
+           !(filp->f_mode & (FMODE_READ|FMODE_WRITE)))
                goto out_putf;
 
        error = flock_make_lock(filp, &lock, cmd);
@@ -1519,7 +1591,7 @@ asmlinkage long sys_flock(unsigned int fd, unsigned int cmd)
        if (can_sleep)
                lock->fl_flags |= FL_SLEEP;
 
-       error = security_file_lock(filp, cmd);
+       error = security_file_lock(filp, lock->fl_type);
        if (error)
                goto out_free;
 
@@ -1531,9 +1603,7 @@ asmlinkage long sys_flock(unsigned int fd, unsigned int cmd)
                error = flock_lock_file_wait(filp, lock);
 
  out_free:
-       if (list_empty(&lock->fl_link)) {
-               locks_free_lock(lock);
-       }
+       locks_free_lock(lock);
 
  out_putf:
        fput(filp);
@@ -1541,12 +1611,62 @@ asmlinkage long sys_flock(unsigned int fd, unsigned int cmd)
        return error;
 }
 
+/**
+ * vfs_test_lock - test file byte range lock
+ * @filp: The file to test lock for
+ * @fl: The lock to test; also used to hold result
+ *
+ * Returns -ERRNO on failure.  Indicates presence of conflicting lock by
+ * setting conf->fl_type to something other than F_UNLCK.
+ */
+int vfs_test_lock(struct file *filp, struct file_lock *fl)
+{
+       if (filp->f_op && filp->f_op->lock)
+               return filp->f_op->lock(filp, F_GETLK, fl);
+       posix_test_lock(filp, fl);
+       return 0;
+}
+EXPORT_SYMBOL_GPL(vfs_test_lock);
+
+static int posix_lock_to_flock(struct flock *flock, struct file_lock *fl)
+{
+       flock->l_pid = fl->fl_pid;
+#if BITS_PER_LONG == 32
+       /*
+        * Make sure we can represent the posix lock via
+        * legacy 32bit flock.
+        */
+       if (fl->fl_start > OFFT_OFFSET_MAX)
+               return -EOVERFLOW;
+       if (fl->fl_end != OFFSET_MAX && fl->fl_end > OFFT_OFFSET_MAX)
+               return -EOVERFLOW;
+#endif
+       flock->l_start = fl->fl_start;
+       flock->l_len = fl->fl_end == OFFSET_MAX ? 0 :
+               fl->fl_end - fl->fl_start + 1;
+       flock->l_whence = 0;
+       flock->l_type = fl->fl_type;
+       return 0;
+}
+
+#if BITS_PER_LONG == 32
+static void posix_lock_to_flock64(struct flock64 *flock, struct file_lock *fl)
+{
+       flock->l_pid = fl->fl_pid;
+       flock->l_start = fl->fl_start;
+       flock->l_len = fl->fl_end == OFFSET_MAX ? 0 :
+               fl->fl_end - fl->fl_start + 1;
+       flock->l_whence = 0;
+       flock->l_type = fl->fl_type;
+}
+#endif
+
 /* Report the first existing lock that would conflict with l.
  * This implements the F_GETLK command of fcntl().
  */
 int fcntl_getlk(struct file *filp, struct flock __user *l)
 {
-       struct file_lock *fl, file_lock;
+       struct file_lock file_lock;
        struct flock flock;
        int error;
 
@@ -1561,38 +1681,15 @@ int fcntl_getlk(struct file *filp, struct flock __user *l)
        if (error)
                goto out;
 
-       if (filp->f_op && filp->f_op->lock) {
-               error = filp->f_op->lock(filp, F_GETLK, &file_lock);
-               if (file_lock.fl_ops && file_lock.fl_ops->fl_release_private)
-                       file_lock.fl_ops->fl_release_private(&file_lock);
-               if (error < 0)
-                       goto out;
-               else
-                 fl = (file_lock.fl_type == F_UNLCK ? NULL : &file_lock);
-       } else {
-               fl = posix_test_lock(filp, &file_lock);
-       }
+       error = vfs_test_lock(filp, &file_lock);
+       if (error)
+               goto out;
  
-       flock.l_type = F_UNLCK;
-       if (fl != NULL) {
-               flock.l_pid = fl->fl_pid;
-#if BITS_PER_LONG == 32
-               /*
-                * Make sure we can represent the posix lock via
-                * legacy 32bit flock.
-                */
-               error = -EOVERFLOW;
-               if (fl->fl_start > OFFT_OFFSET_MAX)
+       flock.l_type = file_lock.fl_type;
+       if (file_lock.fl_type != F_UNLCK) {
+               error = posix_lock_to_flock(&flock, &file_lock);
+               if (error)
                        goto out;
-               if ((fl->fl_end != OFFSET_MAX)
-                   && (fl->fl_end > OFFT_OFFSET_MAX))
-                       goto out;
-#endif
-               flock.l_start = fl->fl_start;
-               flock.l_len = fl->fl_end == OFFSET_MAX ? 0 :
-                       fl->fl_end - fl->fl_start + 1;
-               flock.l_whence = 0;
-               flock.l_type = fl->fl_type;
        }
        error = -EFAULT;
        if (!copy_to_user(l, &flock, sizeof(flock)))
@@ -1601,6 +1698,72 @@ out:
        return error;
 }
 
+/**
+ * vfs_lock_file - file byte range lock
+ * @filp: The file to apply the lock to
+ * @cmd: type of locking operation (F_SETLK, F_GETLK, etc.)
+ * @fl: The lock to be applied
+ * @conf: Place to return a copy of the conflicting lock, if found.
+ *
+ * A caller that doesn't care about the conflicting lock may pass NULL
+ * as the final argument.
+ *
+ * If the filesystem defines a private ->lock() method, then @conf will
+ * be left unchanged; so a caller that cares should initialize it to
+ * some acceptable default.
+ *
+ * To avoid blocking kernel daemons, such as lockd, that need to acquire POSIX
+ * locks, the ->lock() interface may return asynchronously, before the lock has
+ * been granted or denied by the underlying filesystem, if (and only if)
+ * fl_grant is set. Callers expecting ->lock() to return asynchronously
+ * will only use F_SETLK, not F_SETLKW; they will set FL_SLEEP if (and only if)
+ * the request is for a blocking lock. When ->lock() does return asynchronously,
+ * it must return FILE_LOCK_DEFERRED, and call ->fl_grant() when the lock
+ * request completes.
+ * If the request is for non-blocking lock the file system should return
+ * FILE_LOCK_DEFERRED then try to get the lock and call the callback routine
+ * with the result. If the request timed out the callback routine will return a
+ * nonzero return code and the file system should release the lock. The file
+ * system is also responsible to keep a corresponding posix lock when it
+ * grants a lock so the VFS can find out which locks are locally held and do
+ * the correct lock cleanup when required.
+ * The underlying filesystem must not drop the kernel lock or call
+ * ->fl_grant() before returning to the caller with a FILE_LOCK_DEFERRED
+ * return code.
+ */
+int vfs_lock_file(struct file *filp, unsigned int cmd, struct file_lock *fl, struct file_lock *conf)
+{
+       if (filp->f_op && filp->f_op->lock)
+               return filp->f_op->lock(filp, cmd, fl);
+       else
+               return posix_lock_file(filp, fl, conf);
+}
+EXPORT_SYMBOL_GPL(vfs_lock_file);
+
+static int do_lock_file_wait(struct file *filp, unsigned int cmd,
+                            struct file_lock *fl)
+{
+       int error;
+
+       error = security_file_lock(filp, fl->fl_type);
+       if (error)
+               return error;
+
+       for (;;) {
+               error = vfs_lock_file(filp, cmd, fl, NULL);
+               if (error != FILE_LOCK_DEFERRED)
+                       break;
+               error = wait_event_interruptible(fl->fl_wait, !fl->fl_next);
+               if (!error)
+                       continue;
+
+               locks_delete_block(fl);
+               break;
+       }
+
+       return error;
+}
+
 /* Apply the lock described by l to an open file descriptor.
  * This implements both the F_SETLK and F_SETLKW commands of fcntl().
  */
@@ -1610,6 +1773,7 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd,
        struct file_lock *file_lock = locks_alloc_lock();
        struct flock flock;
        struct inode *inode;
+       struct file *f;
        int error;
 
        if (file_lock == NULL)
@@ -1622,14 +1786,12 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd,
        if (copy_from_user(&flock, l, sizeof(flock)))
                goto out;
 
-       inode = filp->f_dentry->d_inode;
+       inode = filp->f_path.dentry->d_inode;
 
        /* Don't allow mandatory locks on files that may be memory mapped
         * and shared.
         */
-       if (IS_MANDLOCK(inode) &&
-           (inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID &&
-           mapping_writably_mapped(filp->f_mapping)) {
+       if (mandatory_lock(inode) && mapping_writably_mapped(filp->f_mapping)) {
                error = -EAGAIN;
                goto out;
        }
@@ -1659,32 +1821,21 @@ again:
                goto out;
        }
 
-       error = security_file_lock(filp, file_lock->fl_type);
-       if (error)
-               goto out;
-
-       if (filp->f_op && filp->f_op->lock != NULL)
-               error = filp->f_op->lock(filp, cmd, file_lock);
-       else {
-               for (;;) {
-                       error = __posix_lock_file(inode, file_lock);
-                       if ((error != -EAGAIN) || (cmd == F_SETLK))
-                               break;
-                       error = wait_event_interruptible(file_lock->fl_wait,
-                                       !file_lock->fl_next);
-                       if (!error)
-                               continue;
-
-                       locks_delete_block(file_lock);
-                       break;
-               }
-       }
+       error = do_lock_file_wait(filp, cmd, file_lock);
 
        /*
         * Attempt to detect a close/fcntl race and recover by
         * releasing the lock that was just acquired.
         */
-       if (!error && fcheck(fd) != filp && flock.l_type != F_UNLCK) {
+       /*
+        * we need that spin_lock here - it prevents reordering between
+        * update of inode->i_flock and check for it done in close().
+        * rcu_read_lock() wouldn't do.
+        */
+       spin_lock(&current->files->file_lock);
+       f = fcheck(fd);
+       spin_unlock(&current->files->file_lock);
+       if (!error && f != filp && flock.l_type != F_UNLCK) {
                flock.l_type = F_UNLCK;
                goto again;
        }
@@ -1700,7 +1851,7 @@ out:
  */
 int fcntl_getlk64(struct file *filp, struct flock64 __user *l)
 {
-       struct file_lock *fl, file_lock;
+       struct file_lock file_lock;
        struct flock64 flock;
        int error;
 
@@ -1715,27 +1866,14 @@ int fcntl_getlk64(struct file *filp, struct flock64 __user *l)
        if (error)
                goto out;
 
-       if (filp->f_op && filp->f_op->lock) {
-               error = filp->f_op->lock(filp, F_GETLK, &file_lock);
-               if (file_lock.fl_ops && file_lock.fl_ops->fl_release_private)
-                       file_lock.fl_ops->fl_release_private(&file_lock);
-               if (error < 0)
-                       goto out;
-               else
-                 fl = (file_lock.fl_type == F_UNLCK ? NULL : &file_lock);
-       } else {
-               fl = posix_test_lock(filp, &file_lock);
-       }
-       flock.l_type = F_UNLCK;
-       if (fl != NULL) {
-               flock.l_pid = fl->fl_pid;
-               flock.l_start = fl->fl_start;
-               flock.l_len = fl->fl_end == OFFSET_MAX ? 0 :
-                       fl->fl_end - fl->fl_start + 1;
-               flock.l_whence = 0;
-               flock.l_type = fl->fl_type;
-       }
+       error = vfs_test_lock(filp, &file_lock);
+       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);
+
        error = -EFAULT;
        if (!copy_to_user(l, &flock, sizeof(flock)))
                error = 0;
@@ -1753,6 +1891,7 @@ int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd,
        struct file_lock *file_lock = locks_alloc_lock();
        struct flock64 flock;
        struct inode *inode;
+       struct file *f;
        int error;
 
        if (file_lock == NULL)
@@ -1765,14 +1904,12 @@ int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd,
        if (copy_from_user(&flock, l, sizeof(flock)))
                goto out;
 
-       inode = filp->f_dentry->d_inode;
+       inode = filp->f_path.dentry->d_inode;
 
        /* Don't allow mandatory locks on files that may be memory mapped
         * and shared.
         */
-       if (IS_MANDLOCK(inode) &&
-           (inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID &&
-           mapping_writably_mapped(filp->f_mapping)) {
+       if (mandatory_lock(inode) && mapping_writably_mapped(filp->f_mapping)) {
                error = -EAGAIN;
                goto out;
        }
@@ -1802,32 +1939,16 @@ again:
                goto out;
        }
 
-       error = security_file_lock(filp, file_lock->fl_type);
-       if (error)
-               goto out;
-
-       if (filp->f_op && filp->f_op->lock != NULL)
-               error = filp->f_op->lock(filp, cmd, file_lock);
-       else {
-               for (;;) {
-                       error = __posix_lock_file(inode, file_lock);
-                       if ((error != -EAGAIN) || (cmd == F_SETLK64))
-                               break;
-                       error = wait_event_interruptible(file_lock->fl_wait,
-                                       !file_lock->fl_next);
-                       if (!error)
-                               continue;
-
-                       locks_delete_block(file_lock);
-                       break;
-               }
-       }
+       error = do_lock_file_wait(filp, cmd, file_lock);
 
        /*
         * Attempt to detect a close/fcntl race and recover by
         * releasing the lock that was just acquired.
         */
-       if (!error && fcheck(fd) != filp && flock.l_type != F_UNLCK) {
+       spin_lock(&current->files->file_lock);
+       f = fcheck(fd);
+       spin_unlock(&current->files->file_lock);
+       if (!error && f != filp && flock.l_type != F_UNLCK) {
                flock.l_type = F_UNLCK;
                goto again;
        }
@@ -1845,19 +1966,18 @@ out:
  */
 void locks_remove_posix(struct file *filp, fl_owner_t owner)
 {
-       struct file_lock lock, **before;
+       struct file_lock lock;
 
        /*
         * If there are no locks held on this file, we don't need to call
         * posix_lock_file().  Another process could be setting a lock on this
         * file at the same time, but we wouldn't remove that lock anyway.
         */
-       before = &filp->f_dentry->d_inode->i_flock;
-       if (*before == NULL)
+       if (!filp->f_path.dentry->d_inode->i_flock)
                return;
 
        lock.fl_type = F_UNLCK;
-       lock.fl_flags = FL_POSIX;
+       lock.fl_flags = FL_POSIX | FL_CLOSE;
        lock.fl_start = 0;
        lock.fl_end = OFFSET_MAX;
        lock.fl_owner = owner;
@@ -1866,25 +1986,8 @@ void locks_remove_posix(struct file *filp, fl_owner_t owner)
        lock.fl_ops = NULL;
        lock.fl_lmops = NULL;
 
-       if (filp->f_op && filp->f_op->lock != NULL) {
-               filp->f_op->lock(filp, F_SETLK, &lock);
-               goto out;
-       }
+       vfs_lock_file(filp, F_SETLK, &lock, NULL);
 
-       /* Can't use posix_lock_file here; we need to remove it no matter
-        * which pid we have.
-        */
-       lock_kernel();
-       while (*before != NULL) {
-               struct file_lock *fl = *before;
-               if (IS_POSIX(fl) && posix_same_owner(fl, &lock)) {
-                       locks_delete_lock(before);
-                       continue;
-               }
-               before = &fl->fl_next;
-       }
-       unlock_kernel();
-out:
        if (lock.fl_ops && lock.fl_ops->fl_release_private)
                lock.fl_ops->fl_release_private(&lock);
 }
@@ -1896,7 +1999,7 @@ EXPORT_SYMBOL(locks_remove_posix);
  */
 void locks_remove_flock(struct file *filp)
 {
-       struct inode * inode = filp->f_dentry->d_inode; 
+       struct inode * inode = filp->f_path.dentry->d_inode;
        struct file_lock *fl;
        struct file_lock **before;
 
@@ -1938,179 +2041,178 @@ 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
  *
  *     lockd needs to block waiting for locks.
  */
-void
+int
 posix_unblock_lock(struct file *filp, struct file_lock *waiter)
 {
-       /* 
-        * A remote machine may cancel the lock request after it's been
-        * granted locally.  If that happens, we need to delete the lock.
-        */
+       int status = 0;
+
        lock_kernel();
-       if (waiter->fl_next) {
+       if (waiter->fl_next)
                __locks_delete_block(waiter);
-               unlock_kernel();
-       } else {
-               unlock_kernel();
-               waiter->fl_type = F_UNLCK;
-               posix_lock_file(filp, waiter);
-       }
+       else
+               status = -ENOENT;
+       unlock_kernel();
+       return status;
 }
 
 EXPORT_SYMBOL(posix_unblock_lock);
 
-static void lock_get_status(char* out, struct file_lock *fl, int id, char *pfx)
+/**
+ * vfs_cancel_lock - file byte range unblock lock
+ * @filp: The file to apply the unblock to
+ * @fl: The lock to be unblocked
+ *
+ * Used by lock managers to cancel blocked requests
+ */
+int vfs_cancel_lock(struct file *filp, struct file_lock *fl)
+{
+       if (filp->f_op && filp->f_op->lock)
+               return filp->f_op->lock(filp, F_CANCELLK, fl);
+       return 0;
+}
+
+EXPORT_SYMBOL_GPL(vfs_cancel_lock);
+
+#ifdef CONFIG_PROC_FS
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+
+static void lock_get_status(struct seq_file *f, struct file_lock *fl,
+                                                       int id, char *pfx)
 {
        struct inode *inode = NULL;
+       unsigned int fl_pid;
+
+       if (fl->fl_nspid)
+               fl_pid = pid_vnr(fl->fl_nspid);
+       else
+               fl_pid = fl->fl_pid;
 
        if (fl->fl_file != NULL)
-               inode = fl->fl_file->f_dentry->d_inode;
+               inode = fl->fl_file->f_path.dentry->d_inode;
 
-       out += sprintf(out, "%d:%s ", id, pfx);
+       seq_printf(f, "%d:%s ", id, pfx);
        if (IS_POSIX(fl)) {
-               out += sprintf(out, "%6s %s ",
+               seq_printf(f, "%6s %s ",
                             (fl->fl_flags & FL_ACCESS) ? "ACCESS" : "POSIX ",
                             (inode == NULL) ? "*NOINODE*" :
-                            (IS_MANDLOCK(inode) &&
-                             (inode->i_mode & (S_IXGRP | S_ISGID)) == S_ISGID) ?
-                            "MANDATORY" : "ADVISORY ");
+                            mandatory_lock(inode) ? "MANDATORY" : "ADVISORY ");
        } else if (IS_FLOCK(fl)) {
                if (fl->fl_type & LOCK_MAND) {
-                       out += sprintf(out, "FLOCK  MSNFS     ");
+                       seq_printf(f, "FLOCK  MSNFS     ");
                } else {
-                       out += sprintf(out, "FLOCK  ADVISORY  ");
+                       seq_printf(f, "FLOCK  ADVISORY  ");
                }
        } else if (IS_LEASE(fl)) {
-               out += sprintf(out, "LEASE  ");
+               seq_printf(f, "LEASE  ");
                if (fl->fl_type & F_INPROGRESS)
-                       out += sprintf(out, "BREAKING  ");
+                       seq_printf(f, "BREAKING  ");
                else if (fl->fl_file)
-                       out += sprintf(out, "ACTIVE    ");
+                       seq_printf(f, "ACTIVE    ");
                else
-                       out += sprintf(out, "BREAKER   ");
+                       seq_printf(f, "BREAKER   ");
        } else {
-               out += sprintf(out, "UNKNOWN UNKNOWN  ");
+               seq_printf(f, "UNKNOWN UNKNOWN  ");
        }
        if (fl->fl_type & LOCK_MAND) {
-               out += sprintf(out, "%s ",
+               seq_printf(f, "%s ",
                               (fl->fl_type & LOCK_READ)
                               ? (fl->fl_type & LOCK_WRITE) ? "RW   " : "READ "
                               : (fl->fl_type & LOCK_WRITE) ? "WRITE" : "NONE ");
        } else {
-               out += sprintf(out, "%s ",
+               seq_printf(f, "%s ",
                               (fl->fl_type & F_INPROGRESS)
                               ? (fl->fl_type & F_UNLCK) ? "UNLCK" : "READ "
                               : (fl->fl_type & F_WRLCK) ? "WRITE" : "READ ");
        }
        if (inode) {
 #ifdef WE_CAN_BREAK_LSLK_NOW
-               out += sprintf(out, "%d %s:%ld ", fl->fl_pid,
+               seq_printf(f, "%d %s:%ld ", fl_pid,
                                inode->i_sb->s_id, inode->i_ino);
 #else
                /* userspace relies on this representation of dev_t ;-( */
-               out += sprintf(out, "%d %02x:%02x:%ld ", fl->fl_pid,
+               seq_printf(f, "%d %02x:%02x:%ld ", fl_pid,
                                MAJOR(inode->i_sb->s_dev),
                                MINOR(inode->i_sb->s_dev), inode->i_ino);
 #endif
        } else {
-               out += sprintf(out, "%d <none>:0 ", fl->fl_pid);
+               seq_printf(f, "%d <none>:0 ", fl_pid);
        }
        if (IS_POSIX(fl)) {
                if (fl->fl_end == OFFSET_MAX)
-                       out += sprintf(out, "%Ld EOF\n", fl->fl_start);
+                       seq_printf(f, "%Ld EOF\n", fl->fl_start);
                else
-                       out += sprintf(out, "%Ld %Ld\n", fl->fl_start,
-                                       fl->fl_end);
+                       seq_printf(f, "%Ld %Ld\n", fl->fl_start, fl->fl_end);
        } else {
-               out += sprintf(out, "0 EOF\n");
+               seq_printf(f, "0 EOF\n");
        }
 }
 
-static void move_lock_status(char **p, off_t* pos, off_t offset)
+static int locks_show(struct seq_file *f, void *v)
 {
-       int len;
-       len = strlen(*p);
-       if(*pos >= offset) {
-               /* the complete line is valid */
-               *p += len;
-               *pos += len;
-               return;
-       }
-       if(*pos+len > offset) {
-               /* use the second part of the line */
-               int i = offset-*pos;
-               memmove(*p,*p+i,len-i);
-               *p += len-i;
-               *pos += len;
-               return;
-       }
-       /* discard the complete line */
-       *pos += len;
+       struct file_lock *fl, *bfl;
+
+       fl = list_entry(v, struct file_lock, fl_link);
+
+       lock_get_status(f, fl, (long)f->private, "");
+
+       list_for_each_entry(bfl, &fl->fl_block, fl_block)
+               lock_get_status(f, bfl, (long)f->private, " ->");
+
+       f->private++;
+       return 0;
 }
 
-/**
- *     get_locks_status        -       reports lock usage in /proc/locks
- *     @buffer: address in userspace to write into
- *     @start: ?
- *     @offset: how far we are through the buffer
- *     @length: how much to read
- */
+static void *locks_start(struct seq_file *f, loff_t *pos)
+{
+       lock_kernel();
+       f->private = (void *)1;
+       return seq_list_start(&file_lock_list, *pos);
+}
 
-int get_locks_status(char *buffer, char **start, off_t offset, int length)
+static void *locks_next(struct seq_file *f, void *v, loff_t *pos)
 {
-       struct list_head *tmp;
-       char *q = buffer;
-       off_t pos = 0;
-       int i = 0;
+       return seq_list_next(v, &file_lock_list, pos);
+}
 
-       lock_kernel();
-       list_for_each(tmp, &file_lock_list) {
-               struct list_head *btmp;
-               struct file_lock *fl = list_entry(tmp, struct file_lock, fl_link);
-               lock_get_status(q, fl, ++i, "");
-               move_lock_status(&q, &pos, offset);
-
-               if(pos >= offset+length)
-                       goto done;
-
-               list_for_each(btmp, &fl->fl_block) {
-                       struct file_lock *bfl = list_entry(btmp,
-                                       struct file_lock, fl_block);
-                       lock_get_status(q, bfl, i, " ->");
-                       move_lock_status(&q, &pos, offset);
-
-                       if(pos >= offset+length)
-                               goto done;
-               }
-       }
-done:
+static void locks_stop(struct seq_file *f, void *v)
+{
        unlock_kernel();
-       *start = buffer;
-       if(q-buffer < length)
-               return (q-buffer);
-       return length;
 }
 
+static const struct seq_operations locks_seq_operations = {
+       .start  = locks_start,
+       .next   = locks_next,
+       .stop   = locks_stop,
+       .show   = locks_show,
+};
+
+static int locks_open(struct inode *inode, struct file *filp)
+{
+       return seq_open(filp, &locks_seq_operations);
+}
+
+static const struct file_operations proc_locks_operations = {
+       .open           = locks_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = seq_release,
+};
+
+static int __init proc_locks_init(void)
+{
+       proc_create("locks", 0, NULL, &proc_locks_operations);
+       return 0;
+}
+module_init(proc_locks_init);
+#endif
+
 /**
  *     lock_may_read - checks that the region is free of locks
  *     @inode: the inode that is being read
@@ -2189,63 +2291,11 @@ int lock_may_write(struct inode *inode, loff_t start, unsigned long len)
 
 EXPORT_SYMBOL(lock_may_write);
 
-static inline void __steal_locks(struct file *file, fl_owner_t from)
-{
-       struct inode *inode = file->f_dentry->d_inode;
-       struct file_lock *fl = inode->i_flock;
-
-       while (fl) {
-               if (fl->fl_file == file && fl->fl_owner == from)
-                       fl->fl_owner = current->files;
-               fl = fl->fl_next;
-       }
-}
-
-/* When getting ready for executing a binary, we make sure that current
- * has a files_struct on its own. Before dropping the old files_struct,
- * we take over ownership of all locks for all file descriptors we own.
- * Note that we may accidentally steal a lock for a file that a sibling
- * has created since the unshare_files() call.
- */
-void steal_locks(fl_owner_t from)
-{
-       struct files_struct *files = current->files;
-       int i, j;
-       struct fdtable *fdt;
-
-       if (from == files)
-               return;
-
-       lock_kernel();
-       j = 0;
-       rcu_read_lock();
-       fdt = files_fdtable(files);
-       for (;;) {
-               unsigned long set;
-               i = j * __NFDBITS;
-               if (i >= fdt->max_fdset || i >= fdt->max_fds)
-                       break;
-               set = fdt->open_fds->fds_bits[j++];
-               while (set) {
-                       if (set & 1) {
-                               struct file *file = fdt->fd[i];
-                               if (file)
-                                       __steal_locks(file, from);
-                       }
-                       i++;
-                       set >>= 1;
-               }
-       }
-       rcu_read_unlock();
-       unlock_kernel();
-}
-EXPORT_SYMBOL(steal_locks);
-
 static int __init filelock_init(void)
 {
        filelock_cache = kmem_cache_create("file_lock_cache",
                        sizeof(struct file_lock), 0, SLAB_PANIC,
-                       init_once, NULL);
+                       init_once);
        return 0;
 }