4 files changed, 28 insertions, 1 deletions

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 650099597dd2..adfe47b21991 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1716,6 +1716,7 @@ static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
         struct inode *inode = mapping->host;
         size_t count = iov_iter_count(iter);
         loff_t offset = iocb->ki_pos;
+        int rw = iov_iter_rw(iter);
         int err;
 
         err = check_direct_IO(inode, iter, offset);
@@ -1729,8 +1730,11 @@ static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 
         trace_f2fs_direct_IO_enter(inode, offset, count, iov_iter_rw(iter));
 
+        down_read(&F2FS_I(inode)->dio_rwsem[rw]);
         err = blockdev_direct_IO(iocb, inode, iter, get_data_block_dio);
-        if (iov_iter_rw(iter) == WRITE) {
+        up_read(&F2FS_I(inode)->dio_rwsem[rw]);
+
+        if (rw == WRITE) {
                 if (err > 0)
                         set_inode_flag(inode, FI_UPDATE_WRITE);
                 else if (err < 0)
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index b4a46b6823dc..211183c4e5c3 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -454,6 +454,7 @@ struct f2fs_inode_info {
         struct list_head inmem_pages;   /* inmemory pages managed by f2fs */
         struct mutex inmem_lock;        /* lock for inmemory pages */
         struct extent_tree *extent_tree;        /* cached extent_tree entry */
+        struct rw_semaphore dio_rwsem[2];/* avoid racing between dio and gc */
 };
 
 static inline void get_extent_info(struct extent_info *ext,
diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index c61213785914..5c8acf754513 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -755,12 +755,32 @@ next_step:
                 /* phase 3 */
                 inode = find_gc_inode(gc_list, dni.ino);
                 if (inode) {
+                        struct f2fs_inode_info *fi = F2FS_I(inode);
+                        bool locked = false;
+
+                        if (S_ISREG(inode->i_mode)) {
+                                if (!down_write_trylock(&fi->dio_rwsem[READ]))
+                                        continue;
+                                if (!down_write_trylock(
+                                                &fi->dio_rwsem[WRITE])) {
+                                        up_write(&fi->dio_rwsem[READ]);
+                                        continue;
+                                }
+                                locked = true;
+                        }
+
                         start_bidx = start_bidx_of_node(nofs, inode)
                                                                 + ofs_in_node;
                         if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
                                 move_encrypted_block(inode, start_bidx);
                         else
                                 move_data_page(inode, start_bidx, gc_type);
+
+                        if (locked) {
+                                up_write(&fi->dio_rwsem[WRITE]);
+                                up_write(&fi->dio_rwsem[READ]);
+                        }
+
                         stat_inc_data_blk_count(sbi, 1, gc_type);
                 }
         }
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 451dfb4041e8..b97c065cbe74 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -579,6 +579,8 @@ static struct inode *f2fs_alloc_inode(struct super_block *sb)
         INIT_LIST_HEAD(&fi->gdirty_list);
         INIT_LIST_HEAD(&fi->inmem_pages);
         mutex_init(&fi->inmem_lock);
+        init_rwsem(&fi->dio_rwsem[READ]);
+        init_rwsem(&fi->dio_rwsem[WRITE]);
 
         /* Will be used by directory only */
         fi->i_dir_level = F2FS_SB(sb)->dir_level;