diff options
author | Paul Mundt <lethal@linux-sh.org> | 2011-09-05 12:52:33 +0900 |
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committer | Paul Mundt <lethal@linux-sh.org> | 2011-09-05 12:52:33 +0900 |
commit | f1e0477a7b7a541f51eea279910eed4ddd010033 (patch) | |
tree | 552841f13496306f0140d5faca82ae9987a81b5e /fs/xfs/mrlock.h | |
parent | b58c580d996655658975aa8042b43b7d579f3986 (diff) | |
parent | 9e79e3e9dd9672b37ac9412e9a926714306551fe (diff) |
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux into rmobile-latest
Diffstat (limited to 'fs/xfs/mrlock.h')
-rw-r--r-- | fs/xfs/mrlock.h | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/fs/xfs/mrlock.h b/fs/xfs/mrlock.h new file mode 100644 index 00000000000..ff6a19873e5 --- /dev/null +++ b/fs/xfs/mrlock.h @@ -0,0 +1,90 @@ +/* + * Copyright (c) 2000-2006 Silicon Graphics, Inc. + * 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 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it would 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 the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ +#ifndef __XFS_SUPPORT_MRLOCK_H__ +#define __XFS_SUPPORT_MRLOCK_H__ + +#include <linux/rwsem.h> + +typedef struct { + struct rw_semaphore mr_lock; +#ifdef DEBUG + int mr_writer; +#endif +} mrlock_t; + +#ifdef DEBUG +#define mrinit(mrp, name) \ + do { (mrp)->mr_writer = 0; init_rwsem(&(mrp)->mr_lock); } while (0) +#else +#define mrinit(mrp, name) \ + do { init_rwsem(&(mrp)->mr_lock); } while (0) +#endif + +#define mrlock_init(mrp, t,n,s) mrinit(mrp, n) +#define mrfree(mrp) do { } while (0) + +static inline void mraccess_nested(mrlock_t *mrp, int subclass) +{ + down_read_nested(&mrp->mr_lock, subclass); +} + +static inline void mrupdate_nested(mrlock_t *mrp, int subclass) +{ + down_write_nested(&mrp->mr_lock, subclass); +#ifdef DEBUG + mrp->mr_writer = 1; +#endif +} + +static inline int mrtryaccess(mrlock_t *mrp) +{ + return down_read_trylock(&mrp->mr_lock); +} + +static inline int mrtryupdate(mrlock_t *mrp) +{ + if (!down_write_trylock(&mrp->mr_lock)) + return 0; +#ifdef DEBUG + mrp->mr_writer = 1; +#endif + return 1; +} + +static inline void mrunlock_excl(mrlock_t *mrp) +{ +#ifdef DEBUG + mrp->mr_writer = 0; +#endif + up_write(&mrp->mr_lock); +} + +static inline void mrunlock_shared(mrlock_t *mrp) +{ + up_read(&mrp->mr_lock); +} + +static inline void mrdemote(mrlock_t *mrp) +{ +#ifdef DEBUG + mrp->mr_writer = 0; +#endif + downgrade_write(&mrp->mr_lock); +} + +#endif /* __XFS_SUPPORT_MRLOCK_H__ */ |