8 files changed, 97 insertions, 86 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index c72ead869507..8fd9fe4282f5 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2900,6 +2900,18 @@ void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans,
 u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags);
 u64 btrfs_get_alloc_profile(struct btrfs_root *root, int data);
 void btrfs_clear_space_info_full(struct btrfs_fs_info *info);
+
+enum btrfs_reserve_flush_enum {
+        /* If we are in the transaction, we can't flush anything.*/
+        BTRFS_RESERVE_NO_FLUSH,
+        /*
+         * Flushing delalloc may cause deadlock somewhere, in this
+         * case, use FLUSH LIMIT
+         */
+        BTRFS_RESERVE_FLUSH_LIMIT,
+        BTRFS_RESERVE_FLUSH_ALL,
+};
+
 int btrfs_check_data_free_space(struct inode *inode, u64 bytes);
 void btrfs_free_reserved_data_space(struct inode *inode, u64 bytes);
 void btrfs_trans_release_metadata(struct btrfs_trans_handle *trans,
@@ -2919,19 +2931,13 @@ struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root,
 void btrfs_free_block_rsv(struct btrfs_root *root,
                           struct btrfs_block_rsv *rsv);
 int btrfs_block_rsv_add(struct btrfs_root *root,
-                        struct btrfs_block_rsv *block_rsv,
-                        u64 num_bytes);
-int btrfs_block_rsv_add_noflush(struct btrfs_root *root,
-                                struct btrfs_block_rsv *block_rsv,
-                                u64 num_bytes);
+                        struct btrfs_block_rsv *block_rsv, u64 num_bytes,
+                        enum btrfs_reserve_flush_enum flush);
 int btrfs_block_rsv_check(struct btrfs_root *root,
                           struct btrfs_block_rsv *block_rsv, int min_factor);
 int btrfs_block_rsv_refill(struct btrfs_root *root,
-                          struct btrfs_block_rsv *block_rsv,
-                          u64 min_reserved);
-int btrfs_block_rsv_refill_noflush(struct btrfs_root *root,
-                                   struct btrfs_block_rsv *block_rsv,
-                                   u64 min_reserved);
+                           struct btrfs_block_rsv *block_rsv, u64 min_reserved,
+                           enum btrfs_reserve_flush_enum flush);
 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
                             struct btrfs_block_rsv *dst_rsv,
                             u64 num_bytes);
diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index 478f66bdc57b..0c6dca550ea1 100644
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -651,7 +651,8 @@ static int btrfs_delayed_inode_reserve_metadata(
          */
         if (!src_rsv || (!trans->bytes_reserved &&
                          src_rsv->type != BTRFS_BLOCK_RSV_DELALLOC)) {
-                ret = btrfs_block_rsv_add_noflush(root, dst_rsv, num_bytes);
+                ret = btrfs_block_rsv_add(root, dst_rsv, num_bytes,
+                                          BTRFS_RESERVE_NO_FLUSH);
                 /*
                  * Since we're under a transaction reserve_metadata_bytes could
                  * try to commit the transaction which will make it return
@@ -686,7 +687,8 @@ static int btrfs_delayed_inode_reserve_metadata(
                  * reserve something strictly for us.  If not be a pain and try
                  * to steal from the delalloc block rsv.
                  */
-                ret = btrfs_block_rsv_add_noflush(root, dst_rsv, num_bytes);
+                ret = btrfs_block_rsv_add(root, dst_rsv, num_bytes,
+                                          BTRFS_RESERVE_NO_FLUSH);
                 if (!ret)
                         goto out;
 
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 2cfcce290aba..2136adda2a0f 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3644,7 +3644,7 @@ out:
 
 static int can_overcommit(struct btrfs_root *root,
                           struct btrfs_space_info *space_info, u64 bytes,
-                          int flush)
+                          enum btrfs_reserve_flush_enum flush)
 {
         u64 profile = btrfs_get_alloc_profile(root, 0);
         u64 avail;
@@ -3672,7 +3672,7 @@ static int can_overcommit(struct btrfs_root *root,
          * 1/2th of the space. If we can flush, don't let us overcommit
          * too much, let it overcommit up to 1/8 of the space.
          */
-        if (flush)
+        if (flush == BTRFS_RESERVE_FLUSH_ALL)
                 avail >>= 3;
         else
                 avail >>= 1;
@@ -3696,6 +3696,7 @@ static void shrink_delalloc(struct btrfs_root *root, u64 to_reclaim, u64 orig,
         long time_left;
         unsigned long nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
         int loops = 0;
+        enum btrfs_reserve_flush_enum flush;
 
         trans = (struct btrfs_trans_handle *)current->journal_info;
         block_rsv = &root->fs_info->delalloc_block_rsv;
@@ -3723,8 +3724,12 @@ static void shrink_delalloc(struct btrfs_root *root, u64 to_reclaim, u64 orig,
                 wait_event(root->fs_info->async_submit_wait,
                            !atomic_read(&root->fs_info->async_delalloc_pages));
 
+                if (!trans)
+                        flush = BTRFS_RESERVE_FLUSH_ALL;
+                else
+                        flush = BTRFS_RESERVE_NO_FLUSH;
                 spin_lock(&space_info->lock);
-                if (can_overcommit(root, space_info, orig, !trans)) {
+                if (can_overcommit(root, space_info, orig, flush)) {
                         spin_unlock(&space_info->lock);
                         break;
                 }
@@ -3882,7 +3887,8 @@ static int flush_space(struct btrfs_root *root,
  */
 static int reserve_metadata_bytes(struct btrfs_root *root,
                                   struct btrfs_block_rsv *block_rsv,
-                                  u64 orig_bytes, int flush)
+                                  u64 orig_bytes,
+                                  enum btrfs_reserve_flush_enum flush)
 {
         struct btrfs_space_info *space_info = block_rsv->space_info;
         u64 used;
@@ -3895,10 +3901,11 @@ again:
         ret = 0;
         spin_lock(&space_info->lock);
         /*
-         * We only want to wait if somebody other than us is flushing and we are
-         * actually alloed to flush.
+         * We only want to wait if somebody other than us is flushing and we
+         * are actually allowed to flush all things.
          */
-        while (flush && !flushing && space_info->flush) {
+        while (flush == BTRFS_RESERVE_FLUSH_ALL && !flushing &&
+               space_info->flush) {
                 spin_unlock(&space_info->lock);
                 /*
                  * If we have a trans handle we can't wait because the flusher
@@ -3964,23 +3971,40 @@ again:
          * Couldn't make our reservation, save our place so while we're trying
          * to reclaim space we can actually use it instead of somebody else
          * stealing it from us.
+         *
+         * We make the other tasks wait for the flush only when we can flush
+         * all things.
          */
-        if (ret && flush) {
+        if (ret && flush == BTRFS_RESERVE_FLUSH_ALL) {
                 flushing = true;
                 space_info->flush = 1;
         }
 
         spin_unlock(&space_info->lock);
 
-        if (!ret || !flush)
+        if (!ret || flush == BTRFS_RESERVE_NO_FLUSH)
                 goto out;
 
         ret = flush_space(root, space_info, num_bytes, orig_bytes,
                           flush_state);
         flush_state++;
+
+        /*
+         * If we are FLUSH_LIMIT, we can not flush delalloc, or the deadlock
+         * would happen. So skip delalloc flush.
+         */
+        if (flush == BTRFS_RESERVE_FLUSH_LIMIT &&
+            (flush_state == FLUSH_DELALLOC ||
+             flush_state == FLUSH_DELALLOC_WAIT))
+                flush_state = ALLOC_CHUNK;
+
         if (!ret)
                 goto again;
-        else if (flush_state <= COMMIT_TRANS)
+        else if (flush == BTRFS_RESERVE_FLUSH_LIMIT &&
+                 flush_state < COMMIT_TRANS)
+                goto again;
+        else if (flush == BTRFS_RESERVE_FLUSH_ALL &&
+                 flush_state <= COMMIT_TRANS)
                 goto again;
 
 out:
@@ -4131,9 +4155,9 @@ void btrfs_free_block_rsv(struct btrfs_root *root,
         kfree(rsv);
 }
 
-static inline int __block_rsv_add(struct btrfs_root *root,
-                                  struct btrfs_block_rsv *block_rsv,
-                                  u64 num_bytes, int flush)
+int btrfs_block_rsv_add(struct btrfs_root *root,
+                        struct btrfs_block_rsv *block_rsv, u64 num_bytes,
+                        enum btrfs_reserve_flush_enum flush)
 {
         int ret;
 
@@ -4149,20 +4173,6 @@ static inline int __block_rsv_add(struct btrfs_root *root,
         return ret;
 }
 
-int btrfs_block_rsv_add(struct btrfs_root *root,
-                        struct btrfs_block_rsv *block_rsv,
-                        u64 num_bytes)
-{
-        return __block_rsv_add(root, block_rsv, num_bytes, 1);
-}
-
-int btrfs_block_rsv_add_noflush(struct btrfs_root *root,
-                                struct btrfs_block_rsv *block_rsv,
-                                u64 num_bytes)
-{
-        return __block_rsv_add(root, block_rsv, num_bytes, 0);
-}
-
 int btrfs_block_rsv_check(struct btrfs_root *root,
                           struct btrfs_block_rsv *block_rsv, int min_factor)
 {
@@ -4181,9 +4191,9 @@ int btrfs_block_rsv_check(struct btrfs_root *root,
         return ret;
 }
 
-static inline int __btrfs_block_rsv_refill(struct btrfs_root *root,
-                                           struct btrfs_block_rsv *block_rsv,
-                                           u64 min_reserved, int flush)
+int btrfs_block_rsv_refill(struct btrfs_root *root,
+                           struct btrfs_block_rsv *block_rsv, u64 min_reserved,
+                           enum btrfs_reserve_flush_enum flush)
 {
         u64 num_bytes = 0;
         int ret = -ENOSPC;
@@ -4211,20 +4221,6 @@ static inline int __btrfs_block_rsv_refill(struct btrfs_root *root,
         return ret;
 }
 
-int btrfs_block_rsv_refill(struct btrfs_root *root,
-                           struct btrfs_block_rsv *block_rsv,
-                           u64 min_reserved)
-{
-        return __btrfs_block_rsv_refill(root, block_rsv, min_reserved, 1);
-}
-
-int btrfs_block_rsv_refill_noflush(struct btrfs_root *root,
-                                   struct btrfs_block_rsv *block_rsv,
-                                   u64 min_reserved)
-{
-        return __btrfs_block_rsv_refill(root, block_rsv, min_reserved, 0);
-}
-
 int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src_rsv,
                             struct btrfs_block_rsv *dst_rsv,
                             u64 num_bytes)
@@ -4515,14 +4511,15 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
         u64 csum_bytes;
         unsigned nr_extents = 0;
         int extra_reserve = 0;
-        int flush = 1;
+        enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_FLUSH_ALL;
         int ret;
 
         /* Need to be holding the i_mutex here if we aren't free space cache */
         if (btrfs_is_free_space_inode(inode))
-                flush = 0;
+                flush = BTRFS_RESERVE_NO_FLUSH;
 
-        if (flush && btrfs_transaction_in_commit(root->fs_info))
+        if (flush != BTRFS_RESERVE_NO_FLUSH &&
+            btrfs_transaction_in_commit(root->fs_info))
                 schedule_timeout(1);
 
         mutex_lock(&BTRFS_I(inode)->delalloc_mutex);
@@ -6252,7 +6249,8 @@ use_block_rsv(struct btrfs_trans_handle *trans,
         block_rsv = get_block_rsv(trans, root);
 
         if (block_rsv->size == 0) {
-                ret = reserve_metadata_bytes(root, block_rsv, blocksize, 0);
+                ret = reserve_metadata_bytes(root, block_rsv, blocksize,
+                                             BTRFS_RESERVE_NO_FLUSH);
                 /*
                  * If we couldn't reserve metadata bytes try and use some from
                  * the global reserve.
@@ -6279,7 +6277,8 @@ use_block_rsv(struct btrfs_trans_handle *trans,
                         printk(KERN_DEBUG "btrfs: block rsv returned %d\n", ret);
                         WARN_ON(1);
                 }
-                ret = reserve_metadata_bytes(root, block_rsv, blocksize, 0);
+                ret = reserve_metadata_bytes(root, block_rsv, blocksize,
+                                             BTRFS_RESERVE_NO_FLUSH);
                 if (!ret) {
                         return block_rsv;
                 } else if (ret && block_rsv != global_rsv) {
diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c
index b1a1c929ba80..d26f67a59e36 100644
--- a/fs/btrfs/inode-map.c
+++ b/fs/btrfs/inode-map.c
@@ -434,8 +434,9 @@ int btrfs_save_ino_cache(struct btrfs_root *root,
          * 3 items for pre-allocation
          */
         trans->bytes_reserved = btrfs_calc_trans_metadata_size(root, 8);
-        ret = btrfs_block_rsv_add_noflush(root, trans->block_rsv,
-                                          trans->bytes_reserved);
+        ret = btrfs_block_rsv_add(root, trans->block_rsv,
+                                  trans->bytes_reserved,
+                                  BTRFS_RESERVE_NO_FLUSH);
         if (ret)
                 goto out;
         trace_btrfs_space_reservation(root->fs_info, "ino_cache",
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 95542a1b3dfc..db3dd4ed057f 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3829,7 +3829,8 @@ void btrfs_evict_inode(struct inode *inode)
          * inode item when doing the truncate.
          */
         while (1) {
-                ret = btrfs_block_rsv_refill_noflush(root, rsv, min_size);
+                ret = btrfs_block_rsv_refill(root, rsv, min_size,
+                                             BTRFS_RESERVE_FLUSH_LIMIT);
 
                 /*
                  * Try and steal from the global reserve since we will
@@ -3847,7 +3848,7 @@ void btrfs_evict_inode(struct inode *inode)
                         goto no_delete;
                 }
 
-                trans = btrfs_start_transaction_noflush(root, 1);
+                trans = btrfs_start_transaction_lflush(root, 1);
                 if (IS_ERR(trans)) {
                         btrfs_orphan_del(NULL, inode);
                         btrfs_free_block_rsv(root, rsv);
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 776f0aa128fc..242d6de4d8eb 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -2074,7 +2074,8 @@ static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
                 BUG_ON(IS_ERR(trans));
                 trans->block_rsv = rc->block_rsv;
 
-                ret = btrfs_block_rsv_refill(root, rc->block_rsv, min_reserved);
+                ret = btrfs_block_rsv_refill(root, rc->block_rsv, min_reserved,
+                                             BTRFS_RESERVE_FLUSH_ALL);
                 if (ret) {
                         BUG_ON(ret != -EAGAIN);
                         ret = btrfs_commit_transaction(trans, root);
@@ -2184,7 +2185,8 @@ int prepare_to_merge(struct reloc_control *rc, int err)
 again:
         if (!err) {
                 num_bytes = rc->merging_rsv_size;
-                ret = btrfs_block_rsv_add(root, rc->block_rsv, num_bytes);
+                ret = btrfs_block_rsv_add(root, rc->block_rsv, num_bytes,
+                                          BTRFS_RESERVE_FLUSH_ALL);
                 if (ret)
                         err = ret;
         }
@@ -2459,7 +2461,8 @@ static int reserve_metadata_space(struct btrfs_trans_handle *trans,
         num_bytes = calcu_metadata_size(rc, node, 1) * 2;
 
         trans->block_rsv = rc->block_rsv;
-        ret = btrfs_block_rsv_add(root, rc->block_rsv, num_bytes);
+        ret = btrfs_block_rsv_add(root, rc->block_rsv, num_bytes,
+                                  BTRFS_RESERVE_FLUSH_ALL);
         if (ret) {
                 if (ret == -EAGAIN)
                         rc->commit_transaction = 1;
@@ -3685,7 +3688,8 @@ int prepare_to_relocate(struct reloc_control *rc)
          * is no reservation in transaction handle.
          */
         ret = btrfs_block_rsv_add(rc->extent_root, rc->block_rsv,
-                                  rc->extent_root->nodesize * 256);
+                                  rc->extent_root->nodesize * 256,
+                                  BTRFS_RESERVE_FLUSH_ALL);
         if (ret)
                 return ret;
 
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 04bbfb1052eb..4e1def4c06b1 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -295,9 +295,9 @@ static int may_wait_transaction(struct btrfs_root *root, int type)
         return 0;
 }
 
-static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
-                                                    u64 num_items, int type,
-                                                    int noflush)
+static struct btrfs_trans_handle *
+start_transaction(struct btrfs_root *root, u64 num_items, int type,
+                  enum btrfs_reserve_flush_enum flush)
 {
         struct btrfs_trans_handle *h;
         struct btrfs_transaction *cur_trans;
@@ -331,14 +331,9 @@ static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
                 }
 
                 num_bytes = btrfs_calc_trans_metadata_size(root, num_items);
-                if (noflush)
-                        ret = btrfs_block_rsv_add_noflush(root,
-                                                &root->fs_info->trans_block_rsv,
-                                                num_bytes);
-                else
-                        ret = btrfs_block_rsv_add(root,
-                                                &root->fs_info->trans_block_rsv,
-                                                num_bytes);
+                ret = btrfs_block_rsv_add(root,
+                                          &root->fs_info->trans_block_rsv,
+                                          num_bytes, flush);
                 if (ret)
                         return ERR_PTR(ret);
         }
@@ -422,13 +417,15 @@ got_it:
 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
                                                    int num_items)
 {
-        return start_transaction(root, num_items, TRANS_START, 0);
+        return start_transaction(root, num_items, TRANS_START,
+                                 BTRFS_RESERVE_FLUSH_ALL);
 }
 
-struct btrfs_trans_handle *btrfs_start_transaction_noflush(
+struct btrfs_trans_handle *btrfs_start_transaction_lflush(
                                         struct btrfs_root *root, int num_items)
 {
-        return start_transaction(root, num_items, TRANS_START, 1);
+        return start_transaction(root, num_items, TRANS_START,
+                                 BTRFS_RESERVE_FLUSH_LIMIT);
 }
 
 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root)
@@ -1032,8 +1029,9 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
         btrfs_reloc_pre_snapshot(trans, pending, &to_reserve);
 
         if (to_reserve > 0) {
-                ret = btrfs_block_rsv_add_noflush(root, &pending->block_rsv,
-                                                  to_reserve);
+                ret = btrfs_block_rsv_add(root, &pending->block_rsv,
+                                          to_reserve,
+                                          BTRFS_RESERVE_NO_FLUSH);
                 if (ret) {
                         pending->error = ret;
                         goto no_free_objectid;
diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h
index 80961947a6b2..0e8aa1e6c287 100644
--- a/fs/btrfs/transaction.h
+++ b/fs/btrfs/transaction.h
@@ -105,7 +105,7 @@ int btrfs_end_transaction(struct btrfs_trans_handle *trans,
                           struct btrfs_root *root);
 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
                                                    int num_items);
-struct btrfs_trans_handle *btrfs_start_transaction_noflush(
+struct btrfs_trans_handle *btrfs_start_transaction_lflush(
                                         struct btrfs_root *root, int num_items);
 struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root);
 struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root);