ext4_file_write_iter: move generic_write_checks() up

simpler that way...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 1f0afc181b7b4fd0030a89f7d2a20513affa90d7..42b1fa33a17a5c6c26169b67955ded4e31efba8d 100644 (file)
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -99,7 +99,7 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
        int overwrite = 0;
        size_t length = iov_iter_count(from);
        ssize_t ret;
-       loff_t pos = iocb->ki_pos;
+       loff_t pos;
 
        /*
         * Unaligned direct AIO must be serialized; see comment above
@@ -109,15 +109,22 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
            ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
            !is_sync_kiocb(iocb) &&
            (file->f_flags & O_APPEND ||
-            ext4_unaligned_aio(inode, from, pos))) {
+            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(file, &iocb->ki_pos, &length);
+       if (ret)
+               goto out;
+
+       if (length == 0)
+               goto out;
+
+       iov_iter_truncate(from, length);
+       pos = iocb->ki_pos;
 
        /*
         * If we have encountered a bitmap-format file, the size limit
@@ -126,18 +133,16 @@ 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 (pos >= sbi->s_bitmap_maxbytes) {
                        ret = -EFBIG;
-                       goto errout;
+                       goto out;
                }
                iov_iter_truncate(from, sbi->s_bitmap_maxbytes - pos);
-               length = iov_iter_count(from);
        }
 
        iocb->private = &overwrite;
        if (o_direct) {
+               length = iov_iter_count(from);
                blk_start_plug(&plug);
 
 
@@ -171,16 +176,7 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
                }
        }
 
-       ret = generic_write_checks(file, &iocb->ki_pos, &length);
-       if (ret)
-               goto out;
-
-       if (length == 0)
-               goto out;
-
-       iov_iter_truncate(from, length);
        ret = __generic_file_write_iter(iocb, from);
-out:
        mutex_unlock(&inode->i_mutex);
 
        if (ret > 0) {
@@ -193,7 +189,12 @@ out:
        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;