Revert "locks: keep a count of locks on the flctx lists"

This reverts commit 9bd0f45b7037fcfa8b575c7e27d0431d6e6dc3bb.

Linus rightly pointed out that I failed to initialize the counters
when adding them, so they don't work as expected. Just revert this
patch for now.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>

4 files changed, 33 insertions, 38 deletions

diff --git a/fs/ceph/locks.c b/fs/ceph/locks.c
index 06ea5cd05cd9..4347039ecc18 100644
--- a/fs/ceph/locks.c
+++ b/fs/ceph/locks.c
@@ -245,6 +245,7 @@ int ceph_flock(struct file *file, int cmd, struct file_lock *fl)
  */
 void ceph_count_locks(struct inode *inode, int *fcntl_count, int *flock_count)
 {
+        struct file_lock *lock;
         struct file_lock_context *ctx;
 
         *fcntl_count = 0;
@@ -252,8 +253,12 @@ void ceph_count_locks(struct inode *inode, int *fcntl_count, int *flock_count)
 
         ctx = inode->i_flctx;
         if (ctx) {
-                *fcntl_count = ctx->flc_posix_cnt;
-                *flock_count = ctx->flc_flock_cnt;
+                spin_lock(&ctx->flc_lock);
+                list_for_each_entry(lock, &ctx->flc_posix, fl_list)
+                        ++(*fcntl_count);
+                list_for_each_entry(lock, &ctx->flc_flock, fl_list)
+                        ++(*flock_count);
+                spin_unlock(&ctx->flc_lock);
         }
         dout("counted %d flock locks and %d fcntl locks",
              *flock_count, *fcntl_count);
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 8fe1f7a21b3e..a94b3e673182 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1129,7 +1129,7 @@ cifs_push_posix_locks(struct cifsFileInfo *cfile)
         struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
         struct file_lock *flock;
         struct file_lock_context *flctx = inode->i_flctx;
-        unsigned int i;
+        unsigned int count = 0, i;
         int rc = 0, xid, type;
         struct list_head locks_to_send, *el;
         struct lock_to_push *lck, *tmp;
@@ -1140,14 +1140,20 @@ cifs_push_posix_locks(struct cifsFileInfo *cfile)
         if (!flctx)
                 goto out;
 
+        spin_lock(&flctx->flc_lock);
+        list_for_each(el, &flctx->flc_posix) {
+                count++;
+        }
+        spin_unlock(&flctx->flc_lock);
+
         INIT_LIST_HEAD(&locks_to_send);
 
         /*
-         * Allocating flc_posix_cnt locks is enough because no FL_POSIX locks
-         * can be added to the list while we are holding cinode->lock_sem that
+         * Allocating count locks is enough because no FL_POSIX locks can be
+         * added to the list while we are holding cinode->lock_sem that
          * protects locking operations of this inode.
          */
-        for (i = 0; i < flctx->flc_posix_cnt; i++) {
+        for (i = 0; i < count; i++) {
                 lck = kmalloc(sizeof(struct lock_to_push), GFP_KERNEL);
                 if (!lck) {
                         rc = -ENOMEM;
diff --git a/fs/locks.c b/fs/locks.c
index 4753218f308e..7998f670812c 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -681,21 +681,18 @@ static void locks_wake_up_blocks(struct file_lock *blocker)
 }
 
 static void
-locks_insert_lock_ctx(struct file_lock *fl, int *counter,
-                      struct list_head *before)
+locks_insert_lock_ctx(struct file_lock *fl, struct list_head *before)
 {
         fl->fl_nspid = get_pid(task_tgid(current));
         list_add_tail(&fl->fl_list, before);
-        ++*counter;
         locks_insert_global_locks(fl);
 }
 
 static void
-locks_unlink_lock_ctx(struct file_lock *fl, int *counter)
+locks_unlink_lock_ctx(struct file_lock *fl)
 {
         locks_delete_global_locks(fl);
         list_del_init(&fl->fl_list);
-        --*counter;
         if (fl->fl_nspid) {
                 put_pid(fl->fl_nspid);
                 fl->fl_nspid = NULL;
@@ -704,10 +701,9 @@ locks_unlink_lock_ctx(struct file_lock *fl, int *counter)
 }
 
 static void
-locks_delete_lock_ctx(struct file_lock *fl, int *counter,
-                      struct list_head *dispose)
+locks_delete_lock_ctx(struct file_lock *fl, struct list_head *dispose)
 {
-        locks_unlink_lock_ctx(fl, counter);
+        locks_unlink_lock_ctx(fl);
         if (dispose)
                 list_add(&fl->fl_list, dispose);
         else
@@ -895,7 +891,7 @@ static int flock_lock_file(struct file *filp, struct file_lock *request)
                 if (request->fl_type == fl->fl_type)
                         goto out;
                 found = true;
-                locks_delete_lock_ctx(fl, &ctx->flc_flock_cnt, &dispose);
+                locks_delete_lock_ctx(fl, &dispose);
                 break;
         }
 
@@ -929,7 +925,7 @@ find_conflict:
         if (request->fl_flags & FL_ACCESS)
                 goto out;
         locks_copy_lock(new_fl, request);
-        locks_insert_lock_ctx(new_fl, &ctx->flc_flock_cnt, &ctx->flc_flock);
+        locks_insert_lock_ctx(new_fl, &ctx->flc_flock);
         new_fl = NULL;
         error = 0;
 
@@ -1046,8 +1042,7 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str
                         else
                                 request->fl_end = fl->fl_end;
                         if (added) {
-                                locks_delete_lock_ctx(fl, &ctx->flc_posix_cnt,
-                                                        &dispose);
+                                locks_delete_lock_ctx(fl, &dispose);
                                 continue;
                         }
                         request = fl;
@@ -1076,8 +1071,7 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str
                                  * one (This may happen several times).
                                  */
                                 if (added) {
-                                        locks_delete_lock_ctx(fl,
-                                                &ctx->flc_posix_cnt, &dispose);
+                                        locks_delete_lock_ctx(fl, &dispose);
                                         continue;
                                 }
                                 /*
@@ -1093,10 +1087,8 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str
                                 locks_copy_lock(new_fl, request);
                                 request = new_fl;
                                 new_fl = NULL;
-                                locks_insert_lock_ctx(request,
-                                        &ctx->flc_posix_cnt, &fl->fl_list);
-                                locks_delete_lock_ctx(fl,
-                                        &ctx->flc_posix_cnt, &dispose);
+                                locks_insert_lock_ctx(request, &fl->fl_list);
+                                locks_delete_lock_ctx(fl, &dispose);
                                 added = true;
                         }
                 }
@@ -1124,8 +1116,7 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str
                         goto out;
                 }
                 locks_copy_lock(new_fl, request);
-                locks_insert_lock_ctx(new_fl, &ctx->flc_posix_cnt,
-                                        &fl->fl_list);
+                locks_insert_lock_ctx(new_fl, &fl->fl_list);
                 new_fl = NULL;
         }
         if (right) {
@@ -1136,8 +1127,7 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str
                         left = new_fl2;
                         new_fl2 = NULL;
                         locks_copy_lock(left, right);
-                        locks_insert_lock_ctx(left, &ctx->flc_posix_cnt,
-                                                &fl->fl_list);
+                        locks_insert_lock_ctx(left, &fl->fl_list);
                 }
                 right->fl_start = request->fl_end + 1;
                 locks_wake_up_blocks(right);
@@ -1321,7 +1311,6 @@ static void lease_clear_pending(struct file_lock *fl, int arg)
 /* We already had a lease on this file; just change its type */
 int lease_modify(struct file_lock *fl, int arg, struct list_head *dispose)
 {
-        struct file_lock_context *flctx;
         int error = assign_type(fl, arg);
 
         if (error)
@@ -1331,7 +1320,6 @@ int lease_modify(struct file_lock *fl, int arg, struct list_head *dispose)
         if (arg == F_UNLCK) {
                 struct file *filp = fl->fl_file;
 
-                flctx = file_inode(filp)->i_flctx;
                 f_delown(filp);
                 filp->f_owner.signum = 0;
                 fasync_helper(0, fl->fl_file, 0, &fl->fl_fasync);
@@ -1339,7 +1327,7 @@ int lease_modify(struct file_lock *fl, int arg, struct list_head *dispose)
                         printk(KERN_ERR "locks_delete_lock: fasync == %p\n", fl->fl_fasync);
                         fl->fl_fasync = NULL;
                 }
-                locks_delete_lock_ctx(fl, &flctx->flc_lease_cnt, dispose);
+                locks_delete_lock_ctx(fl, dispose);
         }
         return 0;
 }
@@ -1456,8 +1444,7 @@ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type)
                         fl->fl_downgrade_time = break_time;
                 }
                 if (fl->fl_lmops->lm_break(fl))
-                        locks_delete_lock_ctx(fl, &ctx->flc_lease_cnt,
-                                                &dispose);
+                        locks_delete_lock_ctx(fl, &dispose);
         }
 
         if (list_empty(&ctx->flc_lease))
@@ -1697,7 +1684,7 @@ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr
         if (!leases_enable)
                 goto out;
 
-        locks_insert_lock_ctx(lease, &ctx->flc_lease_cnt, &ctx->flc_lease);
+        locks_insert_lock_ctx(lease, &ctx->flc_lease);
         /*
          * The check in break_lease() is lockless. It's possible for another
          * open to race in after we did the earlier check for a conflicting
@@ -1710,7 +1697,7 @@ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr
         smp_mb();
         error = check_conflicting_open(dentry, arg, lease->fl_flags);
         if (error) {
-                locks_unlink_lock_ctx(lease, &ctx->flc_lease_cnt);
+                locks_unlink_lock_ctx(lease);
                 goto out;
         }
 
diff --git a/include/linux/fs.h b/include/linux/fs.h
index e49f10cc8a73..a5a303e8a33c 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -969,9 +969,6 @@ struct file_lock_context {
         struct list_head        flc_flock;
         struct list_head        flc_posix;
         struct list_head        flc_lease;
-        int                     flc_flock_cnt;
-        int                     flc_posix_cnt;
-        int                     flc_lease_cnt;
 };
 
 /* The following constant reflects the upper bound of the file/locking space */