1 files changed, 17 insertions, 16 deletions

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 7a6defcf3352..e576d682b353 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -95,11 +95,9 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
         struct inode *inode = file_inode(iocb->ki_filp);
         struct mutex *aio_mutex = NULL;
         struct blk_plug plug;
-        int o_direct = io_is_direct(file);
+        int o_direct = iocb->ki_flags & IOCB_DIRECT;
         int overwrite = 0;
-        size_t length = iov_iter_count(from);
         ssize_t ret;
-        loff_t pos = iocb->ki_pos;
 
         /*
          * Unaligned direct AIO must be serialized; see comment above
@@ -108,16 +106,17 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
         if (o_direct &&
             ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
             !is_sync_kiocb(iocb) &&
-            (file->f_flags & O_APPEND ||
-             ext4_unaligned_aio(inode, from, pos))) {
+            (iocb->ki_flags & IOCB_APPEND ||
+             ext4_unaligned_aio(inode, from, iocb->ki_pos))) {
                 aio_mutex = ext4_aio_mutex(inode);
                 mutex_lock(aio_mutex);
                 ext4_unwritten_wait(inode);
         }
 
         mutex_lock(&inode->i_mutex);
-        if (file->f_flags & O_APPEND)
-                iocb->ki_pos = pos = i_size_read(inode);
+        ret = generic_write_checks(iocb, from);
+        if (ret <= 0)
+                goto out;
 
         /*
          * If we have encountered a bitmap-format file, the size limit
@@ -126,22 +125,19 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
         if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
                 struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 
-                if ((pos > sbi->s_bitmap_maxbytes) ||
-                    (pos == sbi->s_bitmap_maxbytes && length > 0)) {
-                        mutex_unlock(&inode->i_mutex);
+                if (iocb->ki_pos >= sbi->s_bitmap_maxbytes) {
                         ret = -EFBIG;
-                        goto errout;
+                        goto out;
                 }
-
-                if (pos + length > sbi->s_bitmap_maxbytes)
-                        iov_iter_truncate(from, sbi->s_bitmap_maxbytes - pos);
+                iov_iter_truncate(from, sbi->s_bitmap_maxbytes - iocb->ki_pos);
         }
 
         iocb->private = &overwrite;
         if (o_direct) {
+                size_t length = iov_iter_count(from);
+                loff_t pos = iocb->ki_pos;
                 blk_start_plug(&plug);
 
-
                 /* check whether we do a DIO overwrite or not */
                 if (ext4_should_dioread_nolock(inode) && !aio_mutex &&
                     !file->f_mapping->nrpages && pos + length <= i_size_read(inode)) {
@@ -185,7 +181,12 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
         if (o_direct)
                 blk_finish_plug(&plug);
 
-errout:
+        if (aio_mutex)
+                mutex_unlock(aio_mutex);
+        return ret;
+
+out:
+        mutex_unlock(&inode->i_mutex);
         if (aio_mutex)
                 mutex_unlock(aio_mutex);
         return ret;