btrfs: add helper for fs_info->closing

wrap checking of filesystem 'closing' flag and fix a few missing memory
barriers.

Signed-off-by: David Sterba <dsterba@suse.cz>

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 4958ef5..8490ee0 100644 (file)
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2354,6 +2354,15 @@ int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
                        struct btrfs_root *root,
                        struct extent_buffer *node,
                        struct extent_buffer *parent);
+static inline int btrfs_fs_closing(struct btrfs_fs_info *fs_info)
+{
+       /*
+        * Get synced with close_ctree()
+        */
+       smp_mb();
+       return fs_info->closing;
+}
+
 /* root-item.c */
 int btrfs_find_root_ref(struct btrfs_root *tree_root,
                        struct btrfs_path *path,

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index c9173a7..5b9b6b6 100644 (file)
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -366,8 +366,7 @@ again:
        nritems = btrfs_header_nritems(leaf);
 
        while (1) {
-               smp_mb();
-               if (fs_info->closing > 1) {
+               if (btrfs_fs_closing(fs_info) > 1) {
                        last = (u64)-1;
                        break;
                }

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 982b5ea..fa4ef18 100644 (file)
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -129,7 +129,7 @@ int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
        if (!btrfs_test_opt(root, AUTO_DEFRAG))
                return 0;
 
-       if (root->fs_info->closing)
+       if (btrfs_fs_closing(root->fs_info))
                return 0;
 
        if (BTRFS_I(inode)->in_defrag)
@@ -229,7 +229,7 @@ int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info)
                first_ino = defrag->ino + 1;
                rb_erase(&defrag->rb_node, &fs_info->defrag_inodes);
 
-               if (fs_info->closing)
+               if (btrfs_fs_closing(fs_info))
                        goto next_free;
 
                spin_unlock(&fs_info->defrag_inodes_lock);

diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index bffa5c4..ad14473 100644 (file)
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -98,7 +98,7 @@ struct inode *lookup_free_space_inode(struct btrfs_root *root,
                return inode;
 
        spin_lock(&block_group->lock);
-       if (!root->fs_info->closing) {
+       if (!btrfs_fs_closing(root->fs_info)) {
                block_group->inode = igrab(inode);
                block_group->iref = 1;
        }
@@ -493,8 +493,7 @@ int load_free_space_cache(struct btrfs_fs_info *fs_info,
         * If we're unmounting then just return, since this does a search on the
         * normal root and not the commit root and we could deadlock.
         */
-       smp_mb();
-       if (fs_info->closing)
+       if (btrfs_fs_closing(fs_info))
                return 0;
 
        /*
@@ -2513,7 +2512,7 @@ struct inode *lookup_free_ino_inode(struct btrfs_root *root,
                return inode;
 
        spin_lock(&root->cache_lock);
-       if (!root->fs_info->closing)
+       if (!btrfs_fs_closing(root->fs_info))
                root->cache_inode = igrab(inode);
        spin_unlock(&root->cache_lock);
 
@@ -2543,8 +2542,7 @@ int load_free_ino_cache(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
         * If we're unmounting then just return, since this does a search on the
         * normal root and not the commit root and we could deadlock.
         */
-       smp_mb();
-       if (fs_info->closing)
+       if (btrfs_fs_closing(fs_info))
                return 0;
 
        path = btrfs_alloc_path();

diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c
index cb79b89..b4087e0 100644 (file)
--- a/fs/btrfs/inode-map.c
+++ b/fs/btrfs/inode-map.c
@@ -62,8 +62,7 @@ again:
                goto out;
 
        while (1) {
-               smp_mb();
-               if (fs_info->closing)
+               if (btrfs_fs_closing(fs_info))
                        goto out;
 
                leaf = path->nodes[0];

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index a83e44b..02ff4a1 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4266,8 +4266,7 @@ int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc)
        if (BTRFS_I(inode)->dummy_inode)
                return 0;
 
-       smp_mb();
-       if (root->fs_info->closing && is_free_space_inode(root, inode))
+       if (btrfs_fs_closing(root->fs_info) && is_free_space_inode(root, inode))
                nolock = true;
 
        if (wbc->sync_mode == WB_SYNC_ALL) {

diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 1204eab..df50fd1 100644 (file)
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -1183,7 +1183,7 @@ int btrfs_scrub_dev(struct btrfs_root *root, u64 devid, u64 start, u64 end,
        int ret;
        struct btrfs_device *dev;
 
-       if (root->fs_info->closing)
+       if (btrfs_fs_closing(root->fs_info))
                return -EINVAL;
 
        /*

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 2d5c6d2..dd71966 100644 (file)
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -817,7 +817,7 @@ int btrfs_defrag_root(struct btrfs_root *root, int cacheonly)
                btrfs_btree_balance_dirty(info->tree_root, nr);
                cond_resched();
 
-               if (root->fs_info->closing || ret != -EAGAIN)
+               if (btrfs_fs_closing(root->fs_info) || ret != -EAGAIN)
                        break;
        }
        root->defrag_running = 0;