1 files changed, 35 insertions, 2 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 3717b3d4c2ce..aa1fb534f69f 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -7239,7 +7239,7 @@ static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
         u64 start = iblock << inode->i_blkbits;
         u64 lockstart, lockend;
         u64 len = bh_result->b_size;
-        u64 orig_len = len;
+        u64 *outstanding_extents = NULL;
         int unlock_bits = EXTENT_LOCKED;
         int ret = 0;
 
@@ -7251,6 +7251,16 @@ static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
         lockstart = start;
         lockend = start + len - 1;
 
+        if (current->journal_info) {
+                /*
+                 * Need to pull our outstanding extents and set journal_info to NULL so
+                 * that anything that needs to check if there's a transction doesn't get
+                 * confused.
+                 */
+                outstanding_extents = current->journal_info;
+                current->journal_info = NULL;
+        }
+
         /*
          * If this errors out it's because we couldn't invalidate pagecache for
          * this range and we need to fallback to buffered.
@@ -7374,11 +7384,20 @@ unlock:
                 if (start + len > i_size_read(inode))
                         i_size_write(inode, start + len);
 
-                if (len < orig_len) {
+                /*
+                 * If we have an outstanding_extents count still set then we're
+                 * within our reservation, otherwise we need to adjust our inode
+                 * counter appropriately.
+                 */
+                if (*outstanding_extents) {
+                        (*outstanding_extents)--;
+                } else {
                         spin_lock(&BTRFS_I(inode)->lock);
                         BTRFS_I(inode)->outstanding_extents++;
                         spin_unlock(&BTRFS_I(inode)->lock);
                 }
+
+                current->journal_info = outstanding_extents;
                 btrfs_free_reserved_data_space(inode, len);
         }
 
@@ -7402,6 +7421,8 @@ unlock:
 unlock_err:
         clear_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend,
                          unlock_bits, 1, 0, &cached_state, GFP_NOFS);
+        if (outstanding_extents)
+                current->journal_info = outstanding_extents;
         return ret;
 }
 
@@ -8101,6 +8122,7 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
 {
         struct file *file = iocb->ki_filp;
         struct inode *inode = file->f_mapping->host;
+        u64 outstanding_extents = 0;
         size_t count = 0;
         int flags = 0;
         bool wakeup = true;
@@ -8138,6 +8160,16 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
                 ret = btrfs_delalloc_reserve_space(inode, count);
                 if (ret)
                         goto out;
+                outstanding_extents = div64_u64(count +
+                                                BTRFS_MAX_EXTENT_SIZE - 1,
+                                                BTRFS_MAX_EXTENT_SIZE);
+
+                /*
+                 * We need to know how many extents we reserved so that we can
+                 * do the accounting properly if we go over the number we
+                 * originally calculated.  Abuse current->journal_info for this.
+                 */
+                current->journal_info = &outstanding_extents;
         } else if (test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
                                      &BTRFS_I(inode)->runtime_flags)) {
                 inode_dio_done(inode);
@@ -8150,6 +8182,7 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
                         iter, offset, btrfs_get_blocks_direct, NULL,
                         btrfs_submit_direct, flags);
         if (rw & WRITE) {
+                current->journal_info = NULL;
                 if (ret < 0 && ret != -EIOCBQUEUED)
                         btrfs_delalloc_release_space(inode, count);
                 else if (ret >= 0 && (size_t)ret < count)