diff options
Diffstat (limited to 'kernel/fs/xfs/xfs_inode.c')
| -rw-r--r-- | kernel/fs/xfs/xfs_inode.c | 68 |
1 files changed, 51 insertions, 17 deletions
diff --git a/kernel/fs/xfs/xfs_inode.c b/kernel/fs/xfs/xfs_inode.c index 539a85fdd..fec4bfba0 100644 --- a/kernel/fs/xfs/xfs_inode.c +++ b/kernel/fs/xfs/xfs_inode.c @@ -164,7 +164,7 @@ xfs_ilock( (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)); ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); - ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0); + ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0); if (lock_flags & XFS_IOLOCK_EXCL) mrupdate_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags)); @@ -212,7 +212,7 @@ xfs_ilock_nowait( (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)); ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); - ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0); + ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0); if (lock_flags & XFS_IOLOCK_EXCL) { if (!mrtryupdate(&ip->i_iolock)) @@ -281,7 +281,7 @@ xfs_iunlock( (XFS_MMAPLOCK_SHARED | XFS_MMAPLOCK_EXCL)); ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) != (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)); - ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0); + ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_SUBCLASS_MASK)) == 0); ASSERT(lock_flags != 0); if (lock_flags & XFS_IOLOCK_EXCL) @@ -364,30 +364,38 @@ int xfs_lock_delays; /* * Bump the subclass so xfs_lock_inodes() acquires each lock with a different - * value. This shouldn't be called for page fault locking, but we also need to - * ensure we don't overrun the number of lockdep subclasses for the iolock or - * mmaplock as that is limited to 12 by the mmap lock lockdep annotations. + * value. This can be called for any type of inode lock combination, including + * parent locking. Care must be taken to ensure we don't overrun the subclass + * storage fields in the class mask we build. */ static inline int xfs_lock_inumorder(int lock_mode, int subclass) { + int class = 0; + + ASSERT(!(lock_mode & (XFS_ILOCK_PARENT | XFS_ILOCK_RTBITMAP | + XFS_ILOCK_RTSUM))); + if (lock_mode & (XFS_IOLOCK_SHARED|XFS_IOLOCK_EXCL)) { - ASSERT(subclass + XFS_LOCK_INUMORDER < - (1 << (XFS_MMAPLOCK_SHIFT - XFS_IOLOCK_SHIFT))); - lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_IOLOCK_SHIFT; + ASSERT(subclass <= XFS_IOLOCK_MAX_SUBCLASS); + ASSERT(subclass + XFS_IOLOCK_PARENT_VAL < + MAX_LOCKDEP_SUBCLASSES); + class += subclass << XFS_IOLOCK_SHIFT; + if (lock_mode & XFS_IOLOCK_PARENT) + class += XFS_IOLOCK_PARENT_VAL << XFS_IOLOCK_SHIFT; } if (lock_mode & (XFS_MMAPLOCK_SHARED|XFS_MMAPLOCK_EXCL)) { - ASSERT(subclass + XFS_LOCK_INUMORDER < - (1 << (XFS_ILOCK_SHIFT - XFS_MMAPLOCK_SHIFT))); - lock_mode |= (subclass + XFS_LOCK_INUMORDER) << - XFS_MMAPLOCK_SHIFT; + ASSERT(subclass <= XFS_MMAPLOCK_MAX_SUBCLASS); + class += subclass << XFS_MMAPLOCK_SHIFT; } - if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) - lock_mode |= (subclass + XFS_LOCK_INUMORDER) << XFS_ILOCK_SHIFT; + if (lock_mode & (XFS_ILOCK_SHARED|XFS_ILOCK_EXCL)) { + ASSERT(subclass <= XFS_ILOCK_MAX_SUBCLASS); + class += subclass << XFS_ILOCK_SHIFT; + } - return lock_mode; + return (lock_mode & ~XFS_LOCK_SUBCLASS_MASK) | class; } /* @@ -399,6 +407,11 @@ xfs_lock_inumorder(int lock_mode, int subclass) * transaction (such as truncate). This can result in deadlock since the long * running trans might need to wait for the inode we just locked in order to * push the tail and free space in the log. + * + * xfs_lock_inodes() can only be used to lock one type of lock at a time - + * the iolock, the mmaplock or the ilock, but not more than one at a time. If we + * lock more than one at a time, lockdep will report false positives saying we + * have violated locking orders. */ void xfs_lock_inodes( @@ -409,8 +422,29 @@ xfs_lock_inodes( int attempts = 0, i, j, try_lock; xfs_log_item_t *lp; - /* currently supports between 2 and 5 inodes */ + /* + * Currently supports between 2 and 5 inodes with exclusive locking. We + * support an arbitrary depth of locking here, but absolute limits on + * inodes depend on the the type of locking and the limits placed by + * lockdep annotations in xfs_lock_inumorder. These are all checked by + * the asserts. + */ ASSERT(ips && inodes >= 2 && inodes <= 5); + ASSERT(lock_mode & (XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL | + XFS_ILOCK_EXCL)); + ASSERT(!(lock_mode & (XFS_IOLOCK_SHARED | XFS_MMAPLOCK_SHARED | + XFS_ILOCK_SHARED))); + ASSERT(!(lock_mode & XFS_IOLOCK_EXCL) || + inodes <= XFS_IOLOCK_MAX_SUBCLASS + 1); + ASSERT(!(lock_mode & XFS_MMAPLOCK_EXCL) || + inodes <= XFS_MMAPLOCK_MAX_SUBCLASS + 1); + ASSERT(!(lock_mode & XFS_ILOCK_EXCL) || + inodes <= XFS_ILOCK_MAX_SUBCLASS + 1); + + if (lock_mode & XFS_IOLOCK_EXCL) { + ASSERT(!(lock_mode & (XFS_MMAPLOCK_EXCL | XFS_ILOCK_EXCL))); + } else if (lock_mode & XFS_MMAPLOCK_EXCL) + ASSERT(!(lock_mode & XFS_ILOCK_EXCL)); try_lock = 0; i = 0; |