ext4_file_write_iter: move generic_write_checks() up

simpler that way...

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

1 files changed, 20 insertions, 19 deletions

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 1f0afc181b7b..42b1fa33a17a 100644
--- 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;