btrfs: remove no longer needed checks for NULL log context

Since commit 75b463d2b47aef ("btrfs: do not commit logs and transactions
during link and rename operations"), we always pass a non-NULL log context
to btrfs_log_inode_parent() and therefore to all the functions that it
calls. So remove the checks we have all over the place that test for a
NULL log context, making the code shorter and easier to read, as well as
reducing the size of the generated code.

This patch is part of a patch set comprised of the following patches:

  btrfs: check if a log tree exists at inode_logged()
  btrfs: remove no longer needed checks for NULL log context
  btrfs: do not log new dentries when logging that a new name exists
  btrfs: always update the logged transaction when logging new names
  btrfs: avoid expensive search when dropping inode items from log
  btrfs: add helper to truncate inode items when logging inode
  btrfs: avoid expensive search when truncating inode items from the log
  btrfs: avoid search for logged i_size when logging inode if possible
  btrfs: avoid attempt to drop extents when logging inode for the first time
  btrfs: do not commit delayed inode when logging a file in full sync mode

This is patch 2/10 and test results are listed in the change log of the
last patch in the set.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 56a91abec85e22b4eb6a6ea60ad98c68b39db0b4..4d4cab8fd6fa5f47a30d6b23e72b3a6a1e680100 100644 (file)
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -207,7 +207,7 @@ again:
        }
 
        atomic_inc(&root->log_writers);
-       if (ctx && !ctx->logging_new_name) {
+       if (!ctx->logging_new_name) {
                int index = root->log_transid % 2;
                list_add_tail(&ctx->list, &root->log_ctxs[index]);
                ctx->log_transid = root->log_transid;
@@ -3037,9 +3037,6 @@ static void wait_for_writer(struct btrfs_root *root)
 static inline void btrfs_remove_log_ctx(struct btrfs_root *root,
                                        struct btrfs_log_ctx *ctx)
 {
-       if (!ctx)
-               return;
-
        mutex_lock(&root->log_mutex);
        list_del_init(&ctx->list);
        mutex_unlock(&root->log_mutex);
@@ -3782,8 +3779,7 @@ search:
                         */
                        di = btrfs_item_ptr(src, i, struct btrfs_dir_item);
                        btrfs_dir_item_key_to_cpu(src, di, &tmp);
-                       if (ctx &&
-                           (btrfs_dir_transid(src, di) == trans->transid ||
+                       if ((btrfs_dir_transid(src, di) == trans->transid ||
                             btrfs_dir_type(src, di) == BTRFS_FT_DIR) &&
                            tmp.type != BTRFS_ROOT_ITEM_KEY)
                                ctx->log_new_dentries = true;
@@ -5242,7 +5238,7 @@ again:
                                        &other_ino, &other_parent);
                        if (ret < 0) {
                                return ret;
-                       } else if (ret > 0 && ctx &&
+                       } else if (ret > 0 &&
                                   other_ino != btrfs_ino(BTRFS_I(ctx->inode))) {
                                if (ins_nr > 0) {
                                        ins_nr++;
@@ -5583,8 +5579,7 @@ log_extents:
         * So keep it simple for this case and just don't flag the ancestors as
         * logged.
         */
-       if (!ctx ||
-           !(S_ISDIR(inode->vfs_inode.i_mode) && ctx->logging_new_name &&
+       if (!(S_ISDIR(inode->vfs_inode.i_mode) && ctx->logging_new_name &&
              &inode->vfs_inode != ctx->inode)) {
                spin_lock(&inode->lock);
                inode->logged_trans = trans->transid;
@@ -5937,11 +5932,10 @@ static int btrfs_log_all_parents(struct btrfs_trans_handle *trans,
                                continue;
                        }
 
-                       if (ctx)
-                               ctx->log_new_dentries = false;
+                       ctx->log_new_dentries = false;
                        ret = btrfs_log_inode(trans, root, BTRFS_I(dir_inode),
                                              LOG_INODE_ALL, ctx);
-                       if (!ret && ctx && ctx->log_new_dentries)
+                       if (!ret && ctx->log_new_dentries)
                                ret = log_new_dir_dentries(trans, root,
                                                   BTRFS_I(dir_inode), ctx);
                        btrfs_add_delayed_iput(dir_inode);
@@ -6202,7 +6196,7 @@ static int btrfs_log_inode_parent(struct btrfs_trans_handle *trans,
                goto end_trans;
        }
 
-       if (S_ISDIR(inode->vfs_inode.i_mode) && ctx && ctx->log_new_dentries)
+       if (S_ISDIR(inode->vfs_inode.i_mode) && ctx->log_new_dentries)
                log_dentries = true;
 
        /*