Btrfs: use a lock to protect incompat/compat flag of the super block

[linux-2.6-block.git] / fs / btrfs / volumes.c

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 35bb2d4ed29f6ed1a00fabb5491fc40d5d669994..76ded9eb77a7ba7ae467ca3911ddbc9d5e1857a8 100644 (file)
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -684,6 +684,12 @@ int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
                __btrfs_close_devices(fs_devices);
                free_fs_devices(fs_devices);
        }
+       /*
+        * Wait for rcu kworkers under __btrfs_close_devices
+        * to finish all blkdev_puts so device is really
+        * free when umount is done.
+        */
+       rcu_barrier();
        return ret;
 }
 
@@ -711,9 +717,9 @@ static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
                if (!device->name)
                        continue;
 
-               ret = btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
-                                           &bdev, &bh);
-               if (ret)
+               /* Just open everything we can; ignore failures here */
+               if (btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
+                                           &bdev, &bh))
                        continue;
 
                disk_super = (struct btrfs_super_block *)bh->b_data;
@@ -2379,7 +2385,11 @@ static int btrfs_relocate_chunk(struct btrfs_root *root,
                return ret;
 
        trans = btrfs_start_transaction(root, 0);
-       BUG_ON(IS_ERR(trans));
+       if (IS_ERR(trans)) {
+               ret = PTR_ERR(trans);
+               btrfs_std_error(root->fs_info, ret);
+               return ret;
+       }
 
        lock_chunks(root);
 
@@ -3050,7 +3060,8 @@ static void __cancel_balance(struct btrfs_fs_info *fs_info)
 
        unset_balance_control(fs_info);
        ret = del_balance_item(fs_info->tree_root);
-       BUG_ON(ret);
+       if (ret)
+               btrfs_std_error(fs_info, ret);
 
        atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
 }
@@ -3230,6 +3241,11 @@ int btrfs_balance(struct btrfs_balance_control *bctl,
                update_ioctl_balance_args(fs_info, 0, bargs);
        }
 
+       if ((ret && ret != -ECANCELED && ret != -ENOSPC) ||
+           balance_need_close(fs_info)) {
+               __cancel_balance(fs_info);
+       }
+
        wake_up(&fs_info->balance_wait_q);
 
        return ret;
@@ -3658,18 +3674,10 @@ static u32 find_raid56_stripe_len(u32 data_devices, u32 dev_stripe_target)
 
 static void check_raid56_incompat_flag(struct btrfs_fs_info *info, u64 type)
 {
-       u64 features;
-
        if (!(type & (BTRFS_BLOCK_GROUP_RAID5 | BTRFS_BLOCK_GROUP_RAID6)))
                return;
 
-       features = btrfs_super_incompat_flags(info->super_copy);
-       if (features & BTRFS_FEATURE_INCOMPAT_RAID56)
-               return;
-
-       features |= BTRFS_FEATURE_INCOMPAT_RAID56;
-       btrfs_set_super_incompat_flags(info->super_copy, features);
-       printk(KERN_INFO "btrfs: setting RAID5/6 feature flag\n");
+       btrfs_set_fs_incompat(info, RAID56);
 }
 
 static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
@@ -3916,7 +3924,7 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 
        em_tree = &extent_root->fs_info->mapping_tree.map_tree;
        write_lock(&em_tree->lock);
-       ret = add_extent_mapping(em_tree, em);
+       ret = add_extent_mapping(em_tree, em, 0);
        write_unlock(&em_tree->lock);
        if (ret) {
                free_extent_map(em);
@@ -4395,9 +4403,9 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw,
        read_unlock(&em_tree->lock);
 
        if (!em) {
-               printk(KERN_CRIT "btrfs: unable to find logical %llu len %llu\n",
-                      (unsigned long long)logical,
-                      (unsigned long long)*length);
+               btrfs_crit(fs_info, "unable to find logical %llu len %llu",
+                       (unsigned long long)logical,
+                       (unsigned long long)*length);
                BUG();
        }
 
@@ -4919,7 +4927,18 @@ int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
        em = lookup_extent_mapping(em_tree, chunk_start, 1);
        read_unlock(&em_tree->lock);
 
-       BUG_ON(!em || em->start != chunk_start);
+       if (!em) {
+               printk(KERN_ERR "btrfs: couldn't find em for chunk %Lu\n",
+                      chunk_start);
+               return -EIO;
+       }
+
+       if (em->start != chunk_start) {
+               printk(KERN_ERR "btrfs: bad chunk start, em=%Lu, wanted=%Lu\n",
+                      em->start, chunk_start);
+               free_extent_map(em);
+               return -EIO;
+       }
        map = (struct map_lookup *)em->bdev;
 
        length = em->len;
@@ -5281,10 +5300,10 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
        }
 
        if (map_length < length) {
-               printk(KERN_CRIT "btrfs: mapping failed logical %llu bio len %llu "
-                      "len %llu\n", (unsigned long long)logical,
-                      (unsigned long long)length,
-                      (unsigned long long)map_length);
+               btrfs_crit(root->fs_info, "mapping failed logical %llu bio len %llu len %llu",
+                       (unsigned long long)logical,
+                       (unsigned long long)length,
+                       (unsigned long long)map_length);
                BUG();
        }
 
@@ -5449,7 +5468,7 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
        }
 
        write_lock(&map_tree->map_tree.lock);
-       ret = add_extent_mapping(&map_tree->map_tree, em);
+       ret = add_extent_mapping(&map_tree->map_tree, em, 0);
        write_unlock(&map_tree->map_tree.lock);
        BUG_ON(ret); /* Tree corruption */
        free_extent_map(em);
@@ -5556,8 +5575,8 @@ static int read_one_dev(struct btrfs_root *root,
                        return -EIO;
 
                if (!device) {
-                       printk(KERN_WARNING "warning devid %llu missing\n",
-                              (unsigned long long)devid);
+                       btrfs_warn(root->fs_info, "devid %llu missing",
+                               (unsigned long long)devid);
                        device = add_missing_dev(root, devid, dev_uuid);
                        if (!device)
                                return -ENOMEM;