diff options
Diffstat (limited to 'fs/xfs/xfs_iget.c')
-rw-r--r-- | fs/xfs/xfs_iget.c | 251 |
1 files changed, 0 insertions, 251 deletions
diff --git a/fs/xfs/xfs_iget.c b/fs/xfs/xfs_iget.c index 069c5ceb945..ea9a5fa49a4 100644 --- a/fs/xfs/xfs_iget.c +++ b/fs/xfs/xfs_iget.c @@ -453,254 +453,3 @@ out_error_or_again: return error; } -/* - * This is a wrapper routine around the xfs_ilock() routine - * used to centralize some grungy code. It is used in places - * that wish to lock the inode solely for reading the extents. - * The reason these places can't just call xfs_ilock(SHARED) - * is that the inode lock also guards to bringing in of the - * extents from disk for a file in b-tree format. If the inode - * is in b-tree format, then we need to lock the inode exclusively - * until the extents are read in. Locking it exclusively all - * the time would limit our parallelism unnecessarily, though. - * What we do instead is check to see if the extents have been - * read in yet, and only lock the inode exclusively if they - * have not. - * - * The function returns a value which should be given to the - * corresponding xfs_iunlock_map_shared(). This value is - * the mode in which the lock was actually taken. - */ -uint -xfs_ilock_map_shared( - xfs_inode_t *ip) -{ - uint lock_mode; - - if ((ip->i_d.di_format == XFS_DINODE_FMT_BTREE) && - ((ip->i_df.if_flags & XFS_IFEXTENTS) == 0)) { - lock_mode = XFS_ILOCK_EXCL; - } else { - lock_mode = XFS_ILOCK_SHARED; - } - - xfs_ilock(ip, lock_mode); - - return lock_mode; -} - -/* - * This is simply the unlock routine to go with xfs_ilock_map_shared(). - * All it does is call xfs_iunlock() with the given lock_mode. - */ -void -xfs_iunlock_map_shared( - xfs_inode_t *ip, - unsigned int lock_mode) -{ - xfs_iunlock(ip, lock_mode); -} - -/* - * The xfs inode contains 2 locks: a multi-reader lock called the - * i_iolock and a multi-reader lock called the i_lock. This routine - * allows either or both of the locks to be obtained. - * - * The 2 locks should always be ordered so that the IO lock is - * obtained first in order to prevent deadlock. - * - * ip -- the inode being locked - * lock_flags -- this parameter indicates the inode's locks - * to be locked. It can be: - * XFS_IOLOCK_SHARED, - * XFS_IOLOCK_EXCL, - * XFS_ILOCK_SHARED, - * XFS_ILOCK_EXCL, - * XFS_IOLOCK_SHARED | XFS_ILOCK_SHARED, - * XFS_IOLOCK_SHARED | XFS_ILOCK_EXCL, - * XFS_IOLOCK_EXCL | XFS_ILOCK_SHARED, - * XFS_IOLOCK_EXCL | XFS_ILOCK_EXCL - */ -void -xfs_ilock( - xfs_inode_t *ip, - uint lock_flags) -{ - /* - * You can't set both SHARED and EXCL for the same lock, - * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED, - * and XFS_ILOCK_EXCL are valid values to set in lock_flags. - */ - ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) != - (XFS_IOLOCK_SHARED | XFS_IOLOCK_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); - - if (lock_flags & XFS_IOLOCK_EXCL) - mrupdate_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags)); - else if (lock_flags & XFS_IOLOCK_SHARED) - mraccess_nested(&ip->i_iolock, XFS_IOLOCK_DEP(lock_flags)); - - if (lock_flags & XFS_ILOCK_EXCL) - mrupdate_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags)); - else if (lock_flags & XFS_ILOCK_SHARED) - mraccess_nested(&ip->i_lock, XFS_ILOCK_DEP(lock_flags)); - - trace_xfs_ilock(ip, lock_flags, _RET_IP_); -} - -/* - * This is just like xfs_ilock(), except that the caller - * is guaranteed not to sleep. It returns 1 if it gets - * the requested locks and 0 otherwise. If the IO lock is - * obtained but the inode lock cannot be, then the IO lock - * is dropped before returning. - * - * ip -- the inode being locked - * lock_flags -- this parameter indicates the inode's locks to be - * to be locked. See the comment for xfs_ilock() for a list - * of valid values. - */ -int -xfs_ilock_nowait( - xfs_inode_t *ip, - uint lock_flags) -{ - /* - * You can't set both SHARED and EXCL for the same lock, - * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED, - * and XFS_ILOCK_EXCL are valid values to set in lock_flags. - */ - ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) != - (XFS_IOLOCK_SHARED | XFS_IOLOCK_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); - - if (lock_flags & XFS_IOLOCK_EXCL) { - if (!mrtryupdate(&ip->i_iolock)) - goto out; - } else if (lock_flags & XFS_IOLOCK_SHARED) { - if (!mrtryaccess(&ip->i_iolock)) - goto out; - } - if (lock_flags & XFS_ILOCK_EXCL) { - if (!mrtryupdate(&ip->i_lock)) - goto out_undo_iolock; - } else if (lock_flags & XFS_ILOCK_SHARED) { - if (!mrtryaccess(&ip->i_lock)) - goto out_undo_iolock; - } - trace_xfs_ilock_nowait(ip, lock_flags, _RET_IP_); - return 1; - - out_undo_iolock: - if (lock_flags & XFS_IOLOCK_EXCL) - mrunlock_excl(&ip->i_iolock); - else if (lock_flags & XFS_IOLOCK_SHARED) - mrunlock_shared(&ip->i_iolock); - out: - return 0; -} - -/* - * xfs_iunlock() is used to drop the inode locks acquired with - * xfs_ilock() and xfs_ilock_nowait(). The caller must pass - * in the flags given to xfs_ilock() or xfs_ilock_nowait() so - * that we know which locks to drop. - * - * ip -- the inode being unlocked - * lock_flags -- this parameter indicates the inode's locks to be - * to be unlocked. See the comment for xfs_ilock() for a list - * of valid values for this parameter. - * - */ -void -xfs_iunlock( - xfs_inode_t *ip, - uint lock_flags) -{ - /* - * You can't set both SHARED and EXCL for the same lock, - * and only XFS_IOLOCK_SHARED, XFS_IOLOCK_EXCL, XFS_ILOCK_SHARED, - * and XFS_ILOCK_EXCL are valid values to set in lock_flags. - */ - ASSERT((lock_flags & (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL)) != - (XFS_IOLOCK_SHARED | XFS_IOLOCK_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 != 0); - - if (lock_flags & XFS_IOLOCK_EXCL) - mrunlock_excl(&ip->i_iolock); - else if (lock_flags & XFS_IOLOCK_SHARED) - mrunlock_shared(&ip->i_iolock); - - if (lock_flags & XFS_ILOCK_EXCL) - mrunlock_excl(&ip->i_lock); - else if (lock_flags & XFS_ILOCK_SHARED) - mrunlock_shared(&ip->i_lock); - - trace_xfs_iunlock(ip, lock_flags, _RET_IP_); -} - -/* - * give up write locks. the i/o lock cannot be held nested - * if it is being demoted. - */ -void -xfs_ilock_demote( - xfs_inode_t *ip, - uint lock_flags) -{ - ASSERT(lock_flags & (XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL)); - ASSERT((lock_flags & ~(XFS_IOLOCK_EXCL|XFS_ILOCK_EXCL)) == 0); - - if (lock_flags & XFS_ILOCK_EXCL) - mrdemote(&ip->i_lock); - if (lock_flags & XFS_IOLOCK_EXCL) - mrdemote(&ip->i_iolock); - - trace_xfs_ilock_demote(ip, lock_flags, _RET_IP_); -} - -#ifdef DEBUG -int -xfs_isilocked( - xfs_inode_t *ip, - uint lock_flags) -{ - if (lock_flags & (XFS_ILOCK_EXCL|XFS_ILOCK_SHARED)) { - if (!(lock_flags & XFS_ILOCK_SHARED)) - return !!ip->i_lock.mr_writer; - return rwsem_is_locked(&ip->i_lock.mr_lock); - } - - if (lock_flags & (XFS_IOLOCK_EXCL|XFS_IOLOCK_SHARED)) { - if (!(lock_flags & XFS_IOLOCK_SHARED)) - return !!ip->i_iolock.mr_writer; - return rwsem_is_locked(&ip->i_iolock.mr_lock); - } - - ASSERT(0); - return 0; -} -#endif - -void -__xfs_iflock( - struct xfs_inode *ip) -{ - wait_queue_head_t *wq = bit_waitqueue(&ip->i_flags, __XFS_IFLOCK_BIT); - DEFINE_WAIT_BIT(wait, &ip->i_flags, __XFS_IFLOCK_BIT); - - do { - prepare_to_wait_exclusive(wq, &wait.wait, TASK_UNINTERRUPTIBLE); - if (xfs_isiflocked(ip)) - io_schedule(); - } while (!xfs_iflock_nowait(ip)); - - finish_wait(wq, &wait.wait); -} |