diff options
| -rw-r--r-- | fs/xfs/xfs_iget.c | 30 | ||||
| -rw-r--r-- | fs/xfs/xfs_inode.c | 47 | ||||
| -rw-r--r-- | fs/xfs/xfs_vnodeops.c | 21 |
3 files changed, 66 insertions, 32 deletions
diff --git a/fs/xfs/xfs_iget.c b/fs/xfs/xfs_iget.c index 4b0c1881d6d..c1c89dac19c 100644 --- a/fs/xfs/xfs_iget.c +++ b/fs/xfs/xfs_iget.c @@ -237,6 +237,36 @@ again: goto again; } + ASSERT(xfs_iflags_test(ip, XFS_IRECLAIMABLE)); + + /* + * If lookup is racing with unlink, then we + * should return an error immediately so we + * don't remove it from the reclaim list and + * potentially leak the inode. + */ + if ((ip->i_d.di_mode == 0) && + !(flags & XFS_IGET_CREATE)) { + read_unlock(&ih->ih_lock); + return ENOENT; + } + + /* + * There may be transactions sitting in the + * incore log buffers or being flushed to disk + * at this time. We can't clear the + * XFS_IRECLAIMABLE flag until these + * transactions have hit the disk, otherwise we + * will void the guarantee the flag provides + * xfs_iunpin() + */ + if (xfs_ipincount(ip)) { + read_unlock(&ih->ih_lock); + xfs_log_force(mp, 0, + XFS_LOG_FORCE|XFS_LOG_SYNC); + XFS_STATS_INC(xs_ig_frecycle); + goto again; + } vn_trace_exit(vp, "xfs_iget.alloc", (inst_t *)__return_address); diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index 17d2a471751..d72c80dbfbb 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -2741,42 +2741,39 @@ xfs_iunpin( { ASSERT(atomic_read(&ip->i_pincount) > 0); - if (atomic_dec_and_test(&ip->i_pincount)) { + if (atomic_dec_and_lock(&ip->i_pincount, &ip->i_flags_lock)) { + /* - * If the inode is currently being reclaimed, the - * linux inode _and_ the xfs vnode may have been - * freed so we cannot reference either of them safely. - * Hence we should not try to do anything to them - * if the xfs inode is currently in the reclaim - * path. + * If the inode is currently being reclaimed, the link between + * the bhv_vnode and the xfs_inode will be broken after the + * XFS_IRECLAIM* flag is set. Hence, if these flags are not + * set, then we can move forward and mark the linux inode dirty + * knowing that it is still valid as it won't freed until after + * the bhv_vnode<->xfs_inode link is broken in xfs_reclaim. The + * i_flags_lock is used to synchronise the setting of the + * XFS_IRECLAIM* flags and the breaking of the link, and so we + * can execute atomically w.r.t to reclaim by holding this lock + * here. * - * However, we still need to issue the unpin wakeup - * call as the inode reclaim may be blocked waiting for - * the inode to become unpinned. + * However, we still need to issue the unpin wakeup call as the + * inode reclaim may be blocked waiting for the inode to become + * unpinned. */ - struct inode *inode = NULL; - spin_lock(&ip->i_flags_lock); if (!__xfs_iflags_test(ip, XFS_IRECLAIM|XFS_IRECLAIMABLE)) { bhv_vnode_t *vp = XFS_ITOV_NULL(ip); + struct inode *inode = NULL; + + BUG_ON(vp == NULL); + inode = vn_to_inode(vp); + BUG_ON(inode->i_state & I_CLEAR); /* make sync come back and flush this inode */ - if (vp) { - inode = vn_to_inode(vp); - - if (!(inode->i_state & - (I_NEW|I_FREEING|I_CLEAR))) { - inode = igrab(inode); - if (inode) - mark_inode_dirty_sync(inode); - } else - inode = NULL; - } + if (!(inode->i_state & (I_NEW|I_FREEING))) + mark_inode_dirty_sync(inode); } spin_unlock(&ip->i_flags_lock); wake_up(&ip->i_ipin_wait); - if (inode) - iput(inode); } } diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c index 4c5d73cbb90..bda774a04b8 100644 --- a/fs/xfs/xfs_vnodeops.c +++ b/fs/xfs/xfs_vnodeops.c @@ -3827,11 +3827,16 @@ xfs_reclaim( */ xfs_synchronize_atime(ip); - /* If we have nothing to flush with this inode then complete the - * teardown now, otherwise break the link between the xfs inode - * and the linux inode and clean up the xfs inode later. This - * avoids flushing the inode to disk during the delete operation - * itself. + /* + * If we have nothing to flush with this inode then complete the + * teardown now, otherwise break the link between the xfs inode and the + * linux inode and clean up the xfs inode later. This avoids flushing + * the inode to disk during the delete operation itself. + * + * When breaking the link, we need to set the XFS_IRECLAIMABLE flag + * first to ensure that xfs_iunpin() will never see an xfs inode + * that has a linux inode being reclaimed. Synchronisation is provided + * by the i_flags_lock. */ if (!ip->i_update_core && (ip->i_itemp == NULL)) { xfs_ilock(ip, XFS_ILOCK_EXCL); @@ -3840,11 +3845,13 @@ xfs_reclaim( } else { xfs_mount_t *mp = ip->i_mount; - /* Protect sync from us */ + /* Protect sync and unpin from us */ XFS_MOUNT_ILOCK(mp); + spin_lock(&ip->i_flags_lock); + __xfs_iflags_set(ip, XFS_IRECLAIMABLE); vn_bhv_remove(VN_BHV_HEAD(vp), XFS_ITOBHV(ip)); + spin_unlock(&ip->i_flags_lock); list_add_tail(&ip->i_reclaim, &mp->m_del_inodes); - xfs_iflags_set(ip, XFS_IRECLAIMABLE); XFS_MOUNT_IUNLOCK(mp); } return 0; |