From 871480933a1c28f8a9fed4c4d34d06c439a7a422 Mon Sep 17 00:00:00 2001 From: Srikant Patnaik Date: Sun, 11 Jan 2015 12:28:04 +0530 Subject: Moved, renamed, and deleted files The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure. --- ANDROID_3.4.5/fs/btrfs/locking.c | 267 --------------------------------------- 1 file changed, 267 deletions(-) delete mode 100644 ANDROID_3.4.5/fs/btrfs/locking.c (limited to 'ANDROID_3.4.5/fs/btrfs/locking.c') diff --git a/ANDROID_3.4.5/fs/btrfs/locking.c b/ANDROID_3.4.5/fs/btrfs/locking.c deleted file mode 100644 index 272f9112..00000000 --- a/ANDROID_3.4.5/fs/btrfs/locking.c +++ /dev/null @@ -1,267 +0,0 @@ -/* - * Copyright (C) 2008 Oracle. All rights reserved. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public - * License v2 as published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - * - * You should have received a copy of the GNU General Public - * License along with this program; if not, write to the - * Free Software Foundation, Inc., 59 Temple Place - Suite 330, - * Boston, MA 021110-1307, USA. - */ -#include -#include -#include -#include -#include -#include "ctree.h" -#include "extent_io.h" -#include "locking.h" - -void btrfs_assert_tree_read_locked(struct extent_buffer *eb); - -/* - * if we currently have a spinning reader or writer lock - * (indicated by the rw flag) this will bump the count - * of blocking holders and drop the spinlock. - */ -void btrfs_set_lock_blocking_rw(struct extent_buffer *eb, int rw) -{ - if (eb->lock_nested) { - read_lock(&eb->lock); - if (eb->lock_nested && current->pid == eb->lock_owner) { - read_unlock(&eb->lock); - return; - } - read_unlock(&eb->lock); - } - if (rw == BTRFS_WRITE_LOCK) { - if (atomic_read(&eb->blocking_writers) == 0) { - WARN_ON(atomic_read(&eb->spinning_writers) != 1); - atomic_dec(&eb->spinning_writers); - btrfs_assert_tree_locked(eb); - atomic_inc(&eb->blocking_writers); - write_unlock(&eb->lock); - } - } else if (rw == BTRFS_READ_LOCK) { - btrfs_assert_tree_read_locked(eb); - atomic_inc(&eb->blocking_readers); - WARN_ON(atomic_read(&eb->spinning_readers) == 0); - atomic_dec(&eb->spinning_readers); - read_unlock(&eb->lock); - } - return; -} - -/* - * if we currently have a blocking lock, take the spinlock - * and drop our blocking count - */ -void btrfs_clear_lock_blocking_rw(struct extent_buffer *eb, int rw) -{ - if (eb->lock_nested) { - read_lock(&eb->lock); - if (&eb->lock_nested && current->pid == eb->lock_owner) { - read_unlock(&eb->lock); - return; - } - read_unlock(&eb->lock); - } - if (rw == BTRFS_WRITE_LOCK_BLOCKING) { - BUG_ON(atomic_read(&eb->blocking_writers) != 1); - write_lock(&eb->lock); - WARN_ON(atomic_read(&eb->spinning_writers)); - atomic_inc(&eb->spinning_writers); - if (atomic_dec_and_test(&eb->blocking_writers)) - wake_up(&eb->write_lock_wq); - } else if (rw == BTRFS_READ_LOCK_BLOCKING) { - BUG_ON(atomic_read(&eb->blocking_readers) == 0); - read_lock(&eb->lock); - atomic_inc(&eb->spinning_readers); - if (atomic_dec_and_test(&eb->blocking_readers)) - wake_up(&eb->read_lock_wq); - } - return; -} - -/* - * take a spinning read lock. This will wait for any blocking - * writers - */ -void btrfs_tree_read_lock(struct extent_buffer *eb) -{ -again: - read_lock(&eb->lock); - if (atomic_read(&eb->blocking_writers) && - current->pid == eb->lock_owner) { - /* - * This extent is already write-locked by our thread. We allow - * an additional read lock to be added because it's for the same - * thread. btrfs_find_all_roots() depends on this as it may be - * called on a partly (write-)locked tree. - */ - BUG_ON(eb->lock_nested); - eb->lock_nested = 1; - read_unlock(&eb->lock); - return; - } - read_unlock(&eb->lock); - wait_event(eb->write_lock_wq, atomic_read(&eb->blocking_writers) == 0); - read_lock(&eb->lock); - if (atomic_read(&eb->blocking_writers)) { - read_unlock(&eb->lock); - goto again; - } - atomic_inc(&eb->read_locks); - atomic_inc(&eb->spinning_readers); -} - -/* - * returns 1 if we get the read lock and 0 if we don't - * this won't wait for blocking writers - */ -int btrfs_try_tree_read_lock(struct extent_buffer *eb) -{ - if (atomic_read(&eb->blocking_writers)) - return 0; - - read_lock(&eb->lock); - if (atomic_read(&eb->blocking_writers)) { - read_unlock(&eb->lock); - return 0; - } - atomic_inc(&eb->read_locks); - atomic_inc(&eb->spinning_readers); - return 1; -} - -/* - * returns 1 if we get the read lock and 0 if we don't - * this won't wait for blocking writers or readers - */ -int btrfs_try_tree_write_lock(struct extent_buffer *eb) -{ - if (atomic_read(&eb->blocking_writers) || - atomic_read(&eb->blocking_readers)) - return 0; - write_lock(&eb->lock); - if (atomic_read(&eb->blocking_writers) || - atomic_read(&eb->blocking_readers)) { - write_unlock(&eb->lock); - return 0; - } - atomic_inc(&eb->write_locks); - atomic_inc(&eb->spinning_writers); - eb->lock_owner = current->pid; - return 1; -} - -/* - * drop a spinning read lock - */ -void btrfs_tree_read_unlock(struct extent_buffer *eb) -{ - if (eb->lock_nested) { - read_lock(&eb->lock); - if (eb->lock_nested && current->pid == eb->lock_owner) { - eb->lock_nested = 0; - read_unlock(&eb->lock); - return; - } - read_unlock(&eb->lock); - } - btrfs_assert_tree_read_locked(eb); - WARN_ON(atomic_read(&eb->spinning_readers) == 0); - atomic_dec(&eb->spinning_readers); - atomic_dec(&eb->read_locks); - read_unlock(&eb->lock); -} - -/* - * drop a blocking read lock - */ -void btrfs_tree_read_unlock_blocking(struct extent_buffer *eb) -{ - if (eb->lock_nested) { - read_lock(&eb->lock); - if (eb->lock_nested && current->pid == eb->lock_owner) { - eb->lock_nested = 0; - read_unlock(&eb->lock); - return; - } - read_unlock(&eb->lock); - } - btrfs_assert_tree_read_locked(eb); - WARN_ON(atomic_read(&eb->blocking_readers) == 0); - if (atomic_dec_and_test(&eb->blocking_readers)) - wake_up(&eb->read_lock_wq); - atomic_dec(&eb->read_locks); -} - -/* - * take a spinning write lock. This will wait for both - * blocking readers or writers - */ -void btrfs_tree_lock(struct extent_buffer *eb) -{ -again: - wait_event(eb->read_lock_wq, atomic_read(&eb->blocking_readers) == 0); - wait_event(eb->write_lock_wq, atomic_read(&eb->blocking_writers) == 0); - write_lock(&eb->lock); - if (atomic_read(&eb->blocking_readers)) { - write_unlock(&eb->lock); - wait_event(eb->read_lock_wq, - atomic_read(&eb->blocking_readers) == 0); - goto again; - } - if (atomic_read(&eb->blocking_writers)) { - write_unlock(&eb->lock); - wait_event(eb->write_lock_wq, - atomic_read(&eb->blocking_writers) == 0); - goto again; - } - WARN_ON(atomic_read(&eb->spinning_writers)); - atomic_inc(&eb->spinning_writers); - atomic_inc(&eb->write_locks); - eb->lock_owner = current->pid; -} - -/* - * drop a spinning or a blocking write lock. - */ -void btrfs_tree_unlock(struct extent_buffer *eb) -{ - int blockers = atomic_read(&eb->blocking_writers); - - BUG_ON(blockers > 1); - - btrfs_assert_tree_locked(eb); - atomic_dec(&eb->write_locks); - - if (blockers) { - WARN_ON(atomic_read(&eb->spinning_writers)); - atomic_dec(&eb->blocking_writers); - smp_wmb(); - wake_up(&eb->write_lock_wq); - } else { - WARN_ON(atomic_read(&eb->spinning_writers) != 1); - atomic_dec(&eb->spinning_writers); - write_unlock(&eb->lock); - } -} - -void btrfs_assert_tree_locked(struct extent_buffer *eb) -{ - BUG_ON(!atomic_read(&eb->write_locks)); -} - -void btrfs_assert_tree_read_locked(struct extent_buffer *eb) -{ - BUG_ON(!atomic_read(&eb->read_locks)); -} -- cgit