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-rw-r--r--fs/xfs/xfs_iget.c30
-rw-r--r--fs/xfs/xfs_inode.c47
-rw-r--r--fs/xfs/xfs_vnodeops.c21
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;