/* * 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; }
int xfs_ilock_nowait( xfs_inode_t *ip, uint 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; }