Btrfs: Fix nodatacow for the new data=ordered mode

Signed-off-by: Chris Mason <chris.mason@oracle.com>

7 files changed, 74 insertions, 34 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 116aee21bf77..f90e5a7ac161 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1403,7 +1403,8 @@ static inline struct dentry *fdentry(struct file *file) {
 }
 
 /* extent-tree.c */
-int btrfs_cross_ref_exists(struct btrfs_root *root,
+int btrfs_cross_ref_exists(struct btrfs_trans_handle *trans,
+                           struct btrfs_root *root,
                            struct btrfs_key *key, u64 bytenr);
 int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
                          struct btrfs_root *root);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 33cb2ac4cb28..fff219ed61d9 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -893,10 +893,10 @@ out:
         return ret;
 }
 
-int btrfs_cross_ref_exists(struct btrfs_root *root,
+int btrfs_cross_ref_exists(struct btrfs_trans_handle *trans,
+                           struct btrfs_root *root,
                            struct btrfs_key *key, u64 bytenr)
 {
-        struct btrfs_trans_handle *trans;
         struct btrfs_root *old_root;
         struct btrfs_path *path = NULL;
         struct extent_buffer *eb;
@@ -908,6 +908,7 @@ int btrfs_cross_ref_exists(struct btrfs_root *root,
         int level;
         int ret;
 
+        BUG_ON(trans == NULL);
         BUG_ON(key->type != BTRFS_EXTENT_DATA_KEY);
         ret = get_reference_status(root, bytenr, 0, key->objectid,
                                    &min_generation, &ref_count);
@@ -917,7 +918,6 @@ int btrfs_cross_ref_exists(struct btrfs_root *root,
         if (ref_count != 1)
                 return 1;
 
-        trans = btrfs_start_transaction(root, 0);
         old_root = root->dirty_root->root;
         ref_generation = old_root->root_key.offset;
 
@@ -973,7 +973,6 @@ int btrfs_cross_ref_exists(struct btrfs_root *root,
 out:
         if (path)
                 btrfs_free_path(path);
-        btrfs_end_transaction(trans, root);
         return ret;
 }
 
@@ -3320,7 +3319,7 @@ again:
         mutex_unlock(&root->fs_info->alloc_mutex);
 
         btrfs_start_delalloc_inodes(root);
-        btrfs_wait_ordered_extents(tree_root);
+        btrfs_wait_ordered_extents(tree_root, 0);
 
         mutex_lock(&root->fs_info->alloc_mutex);
 
@@ -3407,7 +3406,7 @@ next:
                 btrfs_clean_old_snapshots(tree_root);
 
                 btrfs_start_delalloc_inodes(root);
-                btrfs_wait_ordered_extents(tree_root);
+                btrfs_wait_ordered_extents(tree_root, 0);
 
                 trans = btrfs_start_transaction(tree_root, 1);
                 btrfs_commit_transaction(trans, tree_root);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 4d8ffc01931e..c33053ba3816 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -166,7 +166,7 @@ static int cow_file_range(struct inode *inode, u64 start, u64 end)
 
                 cur_alloc_size = ins.offset;
                 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
-                                               ins.offset);
+                                               ins.offset, 0);
                 BUG_ON(ret);
                 if (num_bytes < cur_alloc_size) {
                         printk("num_bytes %Lu cur_alloc %Lu\n", num_bytes,
@@ -187,31 +187,32 @@ static int run_delalloc_nocow(struct inode *inode, u64 start, u64 end)
         u64 extent_start;
         u64 extent_end;
         u64 bytenr;
-        u64 cow_end;
         u64 loops = 0;
         u64 total_fs_bytes;
         struct btrfs_root *root = BTRFS_I(inode)->root;
         struct btrfs_block_group_cache *block_group;
+        struct btrfs_trans_handle *trans;
         struct extent_buffer *leaf;
         int found_type;
         struct btrfs_path *path;
         struct btrfs_file_extent_item *item;
         int ret;
-        int err;
+        int err = 0;
         struct btrfs_key found_key;
 
         total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
         path = btrfs_alloc_path();
         BUG_ON(!path);
+        trans = btrfs_join_transaction(root, 1);
+        BUG_ON(!trans);
 again:
         ret = btrfs_lookup_file_extent(NULL, root, path,
                                        inode->i_ino, start, 0);
         if (ret < 0) {
-                btrfs_free_path(path);
-                return ret;
+                err = ret;
+                goto out;
         }
 
-        cow_end = end;
         if (ret != 0) {
                 if (path->slots[0] == 0)
                         goto not_found;
@@ -244,12 +245,11 @@ again:
                 if (start < extent_start || start >= extent_end)
                         goto not_found;
 
-                cow_end = min(end, extent_end - 1);
                 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
                 if (bytenr == 0)
                         goto not_found;
 
-                if (btrfs_cross_ref_exists(root, &found_key, bytenr))
+                if (btrfs_cross_ref_exists(trans, root, &found_key, bytenr))
                         goto not_found;
                 /*
                  * we may be called by the resizer, make sure we're inside
@@ -260,24 +260,32 @@ again:
                 if (!block_group || block_group->ro)
                         goto not_found;
 
+                bytenr += btrfs_file_extent_offset(leaf, item);
+                extent_num_bytes = min(end + 1, extent_end) - start;
+                ret = btrfs_add_ordered_extent(inode, start, bytenr,
+                                                extent_num_bytes, 1);
+                if (ret) {
+                        err = ret;
+                        goto out;
+                }
+
+                btrfs_release_path(root, path);
                 start = extent_end;
+                if (start <= end) {
+                        loops++;
+                        goto again;
+                }
         } else {
-                goto not_found;
-        }
-loop:
-        if (start > end) {
+not_found:
+                btrfs_end_transaction(trans, root);
                 btrfs_free_path(path);
-                return 0;
+                return cow_file_range(inode, start, end);
         }
-        btrfs_release_path(root, path);
-        loops++;
-        goto again;
-
-not_found:
-        btrfs_release_path(root, path);
-        cow_file_range(inode, start, end);
-        start = end + 1;
-        goto loop;
+out:
+        WARN_ON(err);
+        btrfs_end_transaction(trans, root);
+        btrfs_free_path(path);
+        return err;
 }
 
 static int run_delalloc_range(struct inode *inode, u64 start, u64 end)
@@ -385,6 +393,11 @@ int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
                 goto mapit;
         }
 
+        if (btrfs_test_opt(root, NODATASUM) ||
+            btrfs_test_flag(inode, NODATASUM)) {
+                goto mapit;
+        }
+
         return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
                                    inode, rw, bio, mirror_num,
                                    __btrfs_submit_bio_hook);
@@ -527,6 +540,8 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
 
         ordered_extent = btrfs_lookup_ordered_extent(inode, start);
         BUG_ON(!ordered_extent);
+        if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags))
+                goto nocow;
 
         lock_extent(io_tree, ordered_extent->file_offset,
                     ordered_extent->file_offset + ordered_extent->len - 1,
@@ -567,6 +582,7 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
         unlock_extent(io_tree, ordered_extent->file_offset,
                     ordered_extent->file_offset + ordered_extent->len - 1,
                     GFP_NOFS);
+nocow:
         add_pending_csums(trans, inode, ordered_extent->file_offset,
                           &ordered_extent->list);
 
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 3932c7cd0fae..59b64c738fd1 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -36,6 +36,7 @@
 #include <linux/bit_spinlock.h>
 #include <linux/version.h>
 #include <linux/xattr.h>
+#include <linux/vmalloc.h>
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index db200e6baf7e..da6d43eb41db 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -152,7 +152,7 @@ static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree,
  * inserted.
  */
 int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
-                             u64 start, u64 len)
+                             u64 start, u64 len, int nocow)
 {
         struct btrfs_ordered_inode_tree *tree;
         struct rb_node *node;
@@ -168,6 +168,8 @@ int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
         entry->start = start;
         entry->len = len;
         entry->inode = inode;
+        if (nocow)
+                set_bit(BTRFS_ORDERED_NOCOW, &entry->flags);
 
         /* one ref for the tree */
         atomic_set(&entry->refs, 1);
@@ -303,10 +305,11 @@ int btrfs_remove_ordered_extent(struct inode *inode,
         return 0;
 }
 
-int btrfs_wait_ordered_extents(struct btrfs_root *root)
+int btrfs_wait_ordered_extents(struct btrfs_root *root, int nocow_only)
 {
         struct list_head splice;
         struct list_head *cur;
+        struct list_head *tmp;
         struct btrfs_ordered_extent *ordered;
         struct inode *inode;
 
@@ -314,10 +317,16 @@ int btrfs_wait_ordered_extents(struct btrfs_root *root)
 
         spin_lock(&root->fs_info->ordered_extent_lock);
         list_splice_init(&root->fs_info->ordered_extents, &splice);
-        while(!list_empty(&splice)) {
+        list_for_each_safe(cur, tmp, &splice) {
                 cur = splice.next;
                 ordered = list_entry(cur, struct btrfs_ordered_extent,
                                      root_extent_list);
+                if (nocow_only &&
+                    !test_bit(BTRFS_ORDERED_NOCOW, &ordered->flags)) {
+                        cond_resched_lock(&root->fs_info->ordered_extent_lock);
+                        continue;
+                }
+
                 list_del_init(&ordered->root_extent_list);
                 atomic_inc(&ordered->refs);
                 inode = ordered->inode;
@@ -338,6 +347,7 @@ int btrfs_wait_ordered_extents(struct btrfs_root *root)
 
                 spin_lock(&root->fs_info->ordered_extent_lock);
         }
+        list_splice_init(&splice, &root->fs_info->ordered_extents);
         spin_unlock(&root->fs_info->ordered_extent_lock);
         return 0;
 }
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index 5efe6b63c74c..fd45519f30a8 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -64,6 +64,8 @@ struct btrfs_ordered_sum {
 
 #define BTRFS_ORDERED_COMPLETE 1 /* set when removed from the tree */
 
+#define BTRFS_ORDERED_NOCOW 2 /* set when we want to write in place */
+
 struct btrfs_ordered_extent {
         /* logical offset in the file */
         u64 file_offset;
@@ -125,7 +127,7 @@ int btrfs_remove_ordered_extent(struct inode *inode,
 int btrfs_dec_test_ordered_pending(struct inode *inode,
                                        u64 file_offset, u64 io_size);
 int btrfs_add_ordered_extent(struct inode *inode, u64 file_offset,
-                             u64 start, u64 len);
+                             u64 start, u64 len, int nocow);
 int btrfs_add_ordered_sum(struct inode *inode,
                           struct btrfs_ordered_extent *entry,
                           struct btrfs_ordered_sum *sum);
@@ -143,5 +145,5 @@ int btrfs_wait_on_page_writeback_range(struct address_space *mapping,
                                        pgoff_t start, pgoff_t end);
 int btrfs_fdatawrite_range(struct address_space *mapping, loff_t start,
                            loff_t end, int sync_mode);
-int btrfs_wait_ordered_extents(struct btrfs_root *root);
+int btrfs_wait_ordered_extents(struct btrfs_root *root, int nocow_only);
 #endif
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index ebf5362da1d2..9d3d08e9f8d1 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -438,6 +438,7 @@ static noinline int add_dirty_roots(struct btrfs_trans_handle *trans,
 
                                 free_extent_buffer(root->commit_root);
                                 root->commit_root = NULL;
+                                root->dirty_root = NULL;
 
                                 spin_lock(&root->list_lock);
                                 list_del_init(&dirty->root->dead_list);
@@ -461,6 +462,7 @@ static noinline int add_dirty_roots(struct btrfs_trans_handle *trans,
                                sizeof(struct btrfs_disk_key));
                         root->root_item.drop_level = 0;
                         root->commit_root = NULL;
+                        root->dirty_root = NULL;
                         root->root_key.offset = root->fs_info->generation;
                         btrfs_set_root_bytenr(&root->root_item,
                                               root->node->start);
@@ -762,7 +764,11 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
         }
 
         do {
+                int snap_pending = 0;
                 joined = cur_trans->num_joined;
+                if (!list_empty(&trans->transaction->pending_snapshots))
+                        snap_pending = 1;
+
                 WARN_ON(cur_trans != trans->transaction);
                 prepare_to_wait(&cur_trans->writer_wait, &wait,
                                 TASK_UNINTERRUPTIBLE);
@@ -774,6 +780,11 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 
                 mutex_unlock(&root->fs_info->trans_mutex);
 
+                if (snap_pending) {
+                        ret = btrfs_wait_ordered_extents(root, 1);
+                        BUG_ON(ret);
+                }
+
                 schedule_timeout(timeout);
 
                 mutex_lock(&root->fs_info->trans_mutex);