Merge branch 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason...
authorLinus Torvalds <torvalds@linux-foundation.org>
Fri, 1 May 2015 14:46:21 +0000 (07:46 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Fri, 1 May 2015 14:46:21 +0000 (07:46 -0700)
Pull btrfs fixes from Chris Mason:
 "A few more btrfs fixes.

  These range from corners Filipe found in the new free space cache
  writeback to a grab bag of fixes from the list"

* 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: btrfs_release_extent_buffer_page didn't free pages of dummy extent
  Btrfs: fill ->last_trans for delayed inode in btrfs_fill_inode.
  btrfs: unlock i_mutex after attempting to delete subvolume during send
  btrfs: check io_ctl_prepare_pages return in __btrfs_write_out_cache
  btrfs: fix race on ENOMEM in alloc_extent_buffer
  btrfs: handle ENOMEM in btrfs_alloc_tree_block
  Btrfs: fix find_free_dev_extent() malfunction in case device tree has hole
  Btrfs: don't check for delalloc_bytes in cache_save_setup
  Btrfs: fix deadlock when starting writeback of bg caches
  Btrfs: fix race between start dirty bg cache writeout and bg deletion

fs/btrfs/delayed-inode.c
fs/btrfs/extent-tree.c
fs/btrfs/extent_io.c
fs/btrfs/free-space-cache.c
fs/btrfs/inode.c
fs/btrfs/ioctl.c
fs/btrfs/volumes.c

index cde698a..a2ae427 100644 (file)
@@ -1802,6 +1802,8 @@ int btrfs_fill_inode(struct inode *inode, u32 *rdev)
        set_nlink(inode, btrfs_stack_inode_nlink(inode_item));
        inode_set_bytes(inode, btrfs_stack_inode_nbytes(inode_item));
        BTRFS_I(inode)->generation = btrfs_stack_inode_generation(inode_item);
+        BTRFS_I(inode)->last_trans = btrfs_stack_inode_transid(inode_item);
+
        inode->i_version = btrfs_stack_inode_sequence(inode_item);
        inode->i_rdev = 0;
        *rdev = btrfs_stack_inode_rdev(inode_item);
index 1eef4ee..0ec8e22 100644 (file)
@@ -3178,8 +3178,8 @@ static int write_one_cache_group(struct btrfs_trans_handle *trans,
        bi = btrfs_item_ptr_offset(leaf, path->slots[0]);
        write_extent_buffer(leaf, &cache->item, bi, sizeof(cache->item));
        btrfs_mark_buffer_dirty(leaf);
-       btrfs_release_path(path);
 fail:
+       btrfs_release_path(path);
        if (ret)
                btrfs_abort_transaction(trans, root, ret);
        return ret;
@@ -3305,8 +3305,7 @@ again:
 
        spin_lock(&block_group->lock);
        if (block_group->cached != BTRFS_CACHE_FINISHED ||
-           !btrfs_test_opt(root, SPACE_CACHE) ||
-           block_group->delalloc_bytes) {
+           !btrfs_test_opt(root, SPACE_CACHE)) {
                /*
                 * don't bother trying to write stuff out _if_
                 * a) we're not cached,
@@ -3408,17 +3407,14 @@ int btrfs_start_dirty_block_groups(struct btrfs_trans_handle *trans,
        int loops = 0;
 
        spin_lock(&cur_trans->dirty_bgs_lock);
-       if (!list_empty(&cur_trans->dirty_bgs)) {
-               list_splice_init(&cur_trans->dirty_bgs, &dirty);
+       if (list_empty(&cur_trans->dirty_bgs)) {
+               spin_unlock(&cur_trans->dirty_bgs_lock);
+               return 0;
        }
+       list_splice_init(&cur_trans->dirty_bgs, &dirty);
        spin_unlock(&cur_trans->dirty_bgs_lock);
 
 again:
-       if (list_empty(&dirty)) {
-               btrfs_free_path(path);
-               return 0;
-       }
-
        /*
         * make sure all the block groups on our dirty list actually
         * exist
@@ -3431,18 +3427,16 @@ again:
                        return -ENOMEM;
        }
 
+       /*
+        * cache_write_mutex is here only to save us from balance or automatic
+        * removal of empty block groups deleting this block group while we are
+        * writing out the cache
+        */
+       mutex_lock(&trans->transaction->cache_write_mutex);
        while (!list_empty(&dirty)) {
                cache = list_first_entry(&dirty,
                                         struct btrfs_block_group_cache,
                                         dirty_list);
-
-               /*
-                * cache_write_mutex is here only to save us from balance
-                * deleting this block group while we are writing out the
-                * cache
-                */
-               mutex_lock(&trans->transaction->cache_write_mutex);
-
                /*
                 * this can happen if something re-dirties a block
                 * group that is already under IO.  Just wait for it to
@@ -3495,7 +3489,6 @@ again:
                }
                if (!ret)
                        ret = write_one_cache_group(trans, root, path, cache);
-               mutex_unlock(&trans->transaction->cache_write_mutex);
 
                /* if its not on the io list, we need to put the block group */
                if (should_put)
@@ -3503,7 +3496,16 @@ again:
 
                if (ret)
                        break;
+
+               /*
+                * Avoid blocking other tasks for too long. It might even save
+                * us from writing caches for block groups that are going to be
+                * removed.
+                */
+               mutex_unlock(&trans->transaction->cache_write_mutex);
+               mutex_lock(&trans->transaction->cache_write_mutex);
        }
+       mutex_unlock(&trans->transaction->cache_write_mutex);
 
        /*
         * go through delayed refs for all the stuff we've just kicked off
@@ -3514,8 +3516,15 @@ again:
                loops++;
                spin_lock(&cur_trans->dirty_bgs_lock);
                list_splice_init(&cur_trans->dirty_bgs, &dirty);
+               /*
+                * dirty_bgs_lock protects us from concurrent block group
+                * deletes too (not just cache_write_mutex).
+                */
+               if (!list_empty(&dirty)) {
+                       spin_unlock(&cur_trans->dirty_bgs_lock);
+                       goto again;
+               }
                spin_unlock(&cur_trans->dirty_bgs_lock);
-               goto again;
        }
 
        btrfs_free_path(path);
@@ -7537,7 +7546,7 @@ static void unuse_block_rsv(struct btrfs_fs_info *fs_info,
  * returns the key for the extent through ins, and a tree buffer for
  * the first block of the extent through buf.
  *
- * returns the tree buffer or NULL.
+ * returns the tree buffer or an ERR_PTR on error.
  */
 struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
                                        struct btrfs_root *root,
@@ -7548,6 +7557,7 @@ struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
        struct btrfs_key ins;
        struct btrfs_block_rsv *block_rsv;
        struct extent_buffer *buf;
+       struct btrfs_delayed_extent_op *extent_op;
        u64 flags = 0;
        int ret;
        u32 blocksize = root->nodesize;
@@ -7568,13 +7578,14 @@ struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
 
        ret = btrfs_reserve_extent(root, blocksize, blocksize,
                                   empty_size, hint, &ins, 0, 0);
-       if (ret) {
-               unuse_block_rsv(root->fs_info, block_rsv, blocksize);
-               return ERR_PTR(ret);
-       }
+       if (ret)
+               goto out_unuse;
 
        buf = btrfs_init_new_buffer(trans, root, ins.objectid, level);
-       BUG_ON(IS_ERR(buf)); /* -ENOMEM */
+       if (IS_ERR(buf)) {
+               ret = PTR_ERR(buf);
+               goto out_free_reserved;
+       }
 
        if (root_objectid == BTRFS_TREE_RELOC_OBJECTID) {
                if (parent == 0)
@@ -7584,9 +7595,11 @@ struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
                BUG_ON(parent > 0);
 
        if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
-               struct btrfs_delayed_extent_op *extent_op;
                extent_op = btrfs_alloc_delayed_extent_op();
-               BUG_ON(!extent_op); /* -ENOMEM */
+               if (!extent_op) {
+                       ret = -ENOMEM;
+                       goto out_free_buf;
+               }
                if (key)
                        memcpy(&extent_op->key, key, sizeof(extent_op->key));
                else
@@ -7601,13 +7614,24 @@ struct extent_buffer *btrfs_alloc_tree_block(struct btrfs_trans_handle *trans,
                extent_op->level = level;
 
                ret = btrfs_add_delayed_tree_ref(root->fs_info, trans,
-                                       ins.objectid,
-                                       ins.offset, parent, root_objectid,
-                                       level, BTRFS_ADD_DELAYED_EXTENT,
-                                       extent_op, 0);
-               BUG_ON(ret); /* -ENOMEM */
+                                                ins.objectid, ins.offset,
+                                                parent, root_objectid, level,
+                                                BTRFS_ADD_DELAYED_EXTENT,
+                                                extent_op, 0);
+               if (ret)
+                       goto out_free_delayed;
        }
        return buf;
+
+out_free_delayed:
+       btrfs_free_delayed_extent_op(extent_op);
+out_free_buf:
+       free_extent_buffer(buf);
+out_free_reserved:
+       btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 0);
+out_unuse:
+       unuse_block_rsv(root->fs_info, block_rsv, blocksize);
+       return ERR_PTR(ret);
 }
 
 struct walk_control {
index 782f3bc..43af5a6 100644 (file)
@@ -4560,36 +4560,37 @@ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb)
        do {
                index--;
                page = eb->pages[index];
-               if (page && mapped) {
+               if (!page)
+                       continue;
+               if (mapped)
                        spin_lock(&page->mapping->private_lock);
+               /*
+                * We do this since we'll remove the pages after we've
+                * removed the eb from the radix tree, so we could race
+                * and have this page now attached to the new eb.  So
+                * only clear page_private if it's still connected to
+                * this eb.
+                */
+               if (PagePrivate(page) &&
+                   page->private == (unsigned long)eb) {
+                       BUG_ON(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
+                       BUG_ON(PageDirty(page));
+                       BUG_ON(PageWriteback(page));
                        /*
-                        * We do this since we'll remove the pages after we've
-                        * removed the eb from the radix tree, so we could race
-                        * and have this page now attached to the new eb.  So
-                        * only clear page_private if it's still connected to
-                        * this eb.
+                        * We need to make sure we haven't be attached
+                        * to a new eb.
                         */
-                       if (PagePrivate(page) &&
-                           page->private == (unsigned long)eb) {
-                               BUG_ON(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
-                               BUG_ON(PageDirty(page));
-                               BUG_ON(PageWriteback(page));
-                               /*
-                                * We need to make sure we haven't be attached
-                                * to a new eb.
-                                */
-                               ClearPagePrivate(page);
-                               set_page_private(page, 0);
-                               /* One for the page private */
-                               page_cache_release(page);
-                       }
-                       spin_unlock(&page->mapping->private_lock);
-
-               }
-               if (page) {
-                       /* One for when we alloced the page */
+                       ClearPagePrivate(page);
+                       set_page_private(page, 0);
+                       /* One for the page private */
                        page_cache_release(page);
                }
+
+               if (mapped)
+                       spin_unlock(&page->mapping->private_lock);
+
+               /* One for when we alloced the page */
+               page_cache_release(page);
        } while (index != 0);
 }
 
@@ -4870,6 +4871,7 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info,
                                mark_extent_buffer_accessed(exists, p);
                                goto free_eb;
                        }
+                       exists = NULL;
 
                        /*
                         * Do this so attach doesn't complain and we need to
@@ -4933,12 +4935,12 @@ again:
        return eb;
 
 free_eb:
+       WARN_ON(!atomic_dec_and_test(&eb->refs));
        for (i = 0; i < num_pages; i++) {
                if (eb->pages[i])
                        unlock_page(eb->pages[i]);
        }
 
-       WARN_ON(!atomic_dec_and_test(&eb->refs));
        btrfs_release_extent_buffer(eb);
        return exists;
 }
index 81fa75a..41c510b 100644 (file)
@@ -1218,7 +1218,7 @@ out:
  *
  * This function writes out a free space cache struct to disk for quick recovery
  * on mount.  This will return 0 if it was successfull in writing the cache out,
- * and -1 if it was not.
+ * or an errno if it was not.
  */
 static int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode,
                                   struct btrfs_free_space_ctl *ctl,
@@ -1235,12 +1235,12 @@ static int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode,
        int must_iput = 0;
 
        if (!i_size_read(inode))
-               return -1;
+               return -EIO;
 
        WARN_ON(io_ctl->pages);
        ret = io_ctl_init(io_ctl, inode, root, 1);
        if (ret)
-               return -1;
+               return ret;
 
        if (block_group && (block_group->flags & BTRFS_BLOCK_GROUP_DATA)) {
                down_write(&block_group->data_rwsem);
@@ -1258,7 +1258,9 @@ static int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode,
        }
 
        /* Lock all pages first so we can lock the extent safely. */
-       io_ctl_prepare_pages(io_ctl, inode, 0);
+       ret = io_ctl_prepare_pages(io_ctl, inode, 0);
+       if (ret)
+               goto out;
 
        lock_extent_bits(&BTRFS_I(inode)->io_tree, 0, i_size_read(inode) - 1,
                         0, &cached_state);
index ada4d24..8bb0136 100644 (file)
@@ -3632,25 +3632,28 @@ static void btrfs_read_locked_inode(struct inode *inode)
        BTRFS_I(inode)->generation = btrfs_inode_generation(leaf, inode_item);
        BTRFS_I(inode)->last_trans = btrfs_inode_transid(leaf, inode_item);
 
+       inode->i_version = btrfs_inode_sequence(leaf, inode_item);
+       inode->i_generation = BTRFS_I(inode)->generation;
+       inode->i_rdev = 0;
+       rdev = btrfs_inode_rdev(leaf, inode_item);
+
+       BTRFS_I(inode)->index_cnt = (u64)-1;
+       BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
+
+cache_index:
        /*
         * If we were modified in the current generation and evicted from memory
         * and then re-read we need to do a full sync since we don't have any
         * idea about which extents were modified before we were evicted from
         * cache.
+        *
+        * This is required for both inode re-read from disk and delayed inode
+        * in delayed_nodes_tree.
         */
        if (BTRFS_I(inode)->last_trans == root->fs_info->generation)
                set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
                        &BTRFS_I(inode)->runtime_flags);
 
-       inode->i_version = btrfs_inode_sequence(leaf, inode_item);
-       inode->i_generation = BTRFS_I(inode)->generation;
-       inode->i_rdev = 0;
-       rdev = btrfs_inode_rdev(leaf, inode_item);
-
-       BTRFS_I(inode)->index_cnt = (u64)-1;
-       BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
-
-cache_index:
        path->slots[0]++;
        if (inode->i_nlink != 1 ||
            path->slots[0] >= btrfs_header_nritems(leaf))
index b05653f..1c22c65 100644 (file)
@@ -2410,7 +2410,7 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file,
                        "Attempt to delete subvolume %llu during send",
                        dest->root_key.objectid);
                err = -EPERM;
-               goto out_dput;
+               goto out_unlock_inode;
        }
 
        d_invalidate(dentry);
@@ -2505,6 +2505,7 @@ out_up_write:
                                root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
                spin_unlock(&dest->root_item_lock);
        }
+out_unlock_inode:
        mutex_unlock(&inode->i_mutex);
        if (!err) {
                shrink_dcache_sb(root->fs_info->sb);
index 8bcd2a0..96aebf3 100644 (file)
@@ -1058,6 +1058,7 @@ static int contains_pending_extent(struct btrfs_trans_handle *trans,
        struct extent_map *em;
        struct list_head *search_list = &trans->transaction->pending_chunks;
        int ret = 0;
+       u64 physical_start = *start;
 
 again:
        list_for_each_entry(em, search_list, list) {
@@ -1068,9 +1069,9 @@ again:
                for (i = 0; i < map->num_stripes; i++) {
                        if (map->stripes[i].dev != device)
                                continue;
-                       if (map->stripes[i].physical >= *start + len ||
+                       if (map->stripes[i].physical >= physical_start + len ||
                            map->stripes[i].physical + em->orig_block_len <=
-                           *start)
+                           physical_start)
                                continue;
                        *start = map->stripes[i].physical +
                                em->orig_block_len;
@@ -1193,8 +1194,14 @@ again:
                         */
                        if (contains_pending_extent(trans, device,
                                                    &search_start,
-                                                   hole_size))
-                               hole_size = 0;
+                                                   hole_size)) {
+                               if (key.offset >= search_start) {
+                                       hole_size = key.offset - search_start;
+                               } else {
+                                       WARN_ON_ONCE(1);
+                                       hole_size = 0;
+                               }
+                       }
 
                        if (hole_size > max_hole_size) {
                                max_hole_start = search_start;