Merge branch 'x86/urgent' into x86/asm, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 41 insertions, 9 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index e28f3d4691af..151b7c71b868 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -5717,6 +5717,7 @@ static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
         char *name_ptr;
         int name_len;
         int is_curr = 0;        /* ctx->pos points to the current index? */
+        bool emitted;
 
         /* FIXME, use a real flag for deciding about the key type */
         if (root->fs_info->tree_root == root)
@@ -5745,6 +5746,7 @@ static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
         if (ret < 0)
                 goto err;
 
+        emitted = false;
         while (1) {
                 leaf = path->nodes[0];
                 slot = path->slots[0];
@@ -5824,6 +5826,7 @@ skip:
 
                         if (over)
                                 goto nopos;
+                        emitted = true;
                         di_len = btrfs_dir_name_len(leaf, di) +
                                  btrfs_dir_data_len(leaf, di) + sizeof(*di);
                         di_cur += di_len;
@@ -5836,11 +5839,20 @@ next:
         if (key_type == BTRFS_DIR_INDEX_KEY) {
                 if (is_curr)
                         ctx->pos++;
-                ret = btrfs_readdir_delayed_dir_index(ctx, &ins_list);
+                ret = btrfs_readdir_delayed_dir_index(ctx, &ins_list, &emitted);
                 if (ret)
                         goto nopos;
         }
 
+        /*
+         * If we haven't emitted any dir entry, we must not touch ctx->pos as
+         * it was was set to the termination value in previous call. We assume
+         * that "." and ".." were emitted if we reach this point and set the
+         * termination value as well for an empty directory.
+         */
+        if (ctx->pos > 2 && !emitted)
+                goto nopos;
+
         /* Reached end of directory/root. Bump pos past the last item. */
         ctx->pos++;
 
@@ -7116,21 +7128,41 @@ static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
         if (ret)
                 return ERR_PTR(ret);
 
-        em = create_pinned_em(inode, start, ins.offset, start, ins.objectid,
-                              ins.offset, ins.offset, ins.offset, 0);
-        if (IS_ERR(em)) {
-                btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 1);
-                return em;
-        }
-
+        /*
+         * Create the ordered extent before the extent map. This is to avoid
+         * races with the fast fsync path that would lead to it logging file
+         * extent items that point to disk extents that were not yet written to.
+         * The fast fsync path collects ordered extents into a local list and
+         * then collects all the new extent maps, so we must create the ordered
+         * extent first and make sure the fast fsync path collects any new
+         * ordered extents after collecting new extent maps as well.
+         * The fsync path simply can not rely on inode_dio_wait() because it
+         * causes deadlock with AIO.
+         */
         ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
                                            ins.offset, ins.offset, 0);
         if (ret) {
                 btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 1);
-                free_extent_map(em);
                 return ERR_PTR(ret);
         }
 
+        em = create_pinned_em(inode, start, ins.offset, start, ins.objectid,
+                              ins.offset, ins.offset, ins.offset, 0);
+        if (IS_ERR(em)) {
+                struct btrfs_ordered_extent *oe;
+
+                btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 1);
+                oe = btrfs_lookup_ordered_extent(inode, start);
+                ASSERT(oe);
+                if (WARN_ON(!oe))
+                        return em;
+                set_bit(BTRFS_ORDERED_IOERR, &oe->flags);
+                set_bit(BTRFS_ORDERED_IO_DONE, &oe->flags);
+                btrfs_remove_ordered_extent(inode, oe);
+                /* Once for our lookup and once for the ordered extents tree. */
+                btrfs_put_ordered_extent(oe);
+                btrfs_put_ordered_extent(oe);
+        }
         return em;
 }