提交 8ad2850f 编写于 作者: T Theodore Ts'o

ext4: move ext4_file_dio_write() into ext4_file_write()

This commit doesn't actually change anything; it just moves code
around in preparation for some code simplification work.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: NJan Kara <jack@suse.cz>
上级 7608e610
......@@ -92,82 +92,15 @@ ext4_unaligned_aio(struct inode *inode, const struct iovec *iov,
}
static ssize_t
ext4_file_dio_write(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos)
ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_mapping->host;
struct inode *inode = file_inode(iocb->ki_filp);
struct blk_plug plug;
int unaligned_aio = 0;
ssize_t ret;
int overwrite = 0;
size_t length = iov_length(iov, nr_segs);
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
!is_sync_kiocb(iocb))
unaligned_aio = ext4_unaligned_aio(inode, iov, nr_segs, pos);
/* Unaligned direct AIO must be serialized; see comment above */
if (unaligned_aio) {
mutex_lock(ext4_aio_mutex(inode));
ext4_unwritten_wait(inode);
}
mutex_lock(&inode->i_mutex);
blk_start_plug(&plug);
iocb->private = &overwrite;
/* check whether we do a DIO overwrite or not */
if (ext4_should_dioread_nolock(inode) && !unaligned_aio &&
!file->f_mapping->nrpages && pos + length <= i_size_read(inode)) {
struct ext4_map_blocks map;
unsigned int blkbits = inode->i_blkbits;
int err, len;
map.m_lblk = pos >> blkbits;
map.m_len = (EXT4_BLOCK_ALIGN(pos + length, blkbits) >> blkbits)
- map.m_lblk;
len = map.m_len;
err = ext4_map_blocks(NULL, inode, &map, 0);
/*
* 'err==len' means that all of blocks has been preallocated no
* matter they are initialized or not. For excluding
* unwritten extents, we need to check m_flags. There are
* two conditions that indicate for initialized extents.
* 1) If we hit extent cache, EXT4_MAP_MAPPED flag is returned;
* 2) If we do a real lookup, non-flags are returned.
* So we should check these two conditions.
*/
if (err == len && (map.m_flags & EXT4_MAP_MAPPED))
overwrite = 1;
}
ret = __generic_file_aio_write(iocb, iov, nr_segs);
mutex_unlock(&inode->i_mutex);
if (ret > 0) {
ssize_t err;
err = generic_write_sync(file, iocb->ki_pos - ret, ret);
if (err < 0)
ret = err;
}
blk_finish_plug(&plug);
if (unaligned_aio)
mutex_unlock(ext4_aio_mutex(inode));
return ret;
}
static ssize_t
ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
unsigned long nr_segs, loff_t pos)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file_inode(iocb->ki_filp);
ssize_t ret;
BUG_ON(iocb->ki_pos != pos);
......@@ -179,7 +112,6 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
size_t length = iov_length(iov, nr_segs);
if ((pos > sbi->s_bitmap_maxbytes ||
(pos == sbi->s_bitmap_maxbytes && length > 0)))
......@@ -191,9 +123,67 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
}
}
if (unlikely(iocb->ki_filp->f_flags & O_DIRECT))
ret = ext4_file_dio_write(iocb, iov, nr_segs, pos);
else {
if (unlikely(iocb->ki_filp->f_flags & O_DIRECT)) {
if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
!is_sync_kiocb(iocb))
unaligned_aio = ext4_unaligned_aio(inode, iov,
nr_segs, pos);
/* Unaligned direct AIO must be serialized; see comment above */
if (unaligned_aio) {
mutex_lock(ext4_aio_mutex(inode));
ext4_unwritten_wait(inode);
}
mutex_lock(&inode->i_mutex);
blk_start_plug(&plug);
iocb->private = &overwrite;
/* check whether we do a DIO overwrite or not */
if (ext4_should_dioread_nolock(inode) && !unaligned_aio &&
!file->f_mapping->nrpages && pos + length <= i_size_read(inode)) {
struct ext4_map_blocks map;
unsigned int blkbits = inode->i_blkbits;
int err, len;
map.m_lblk = pos >> blkbits;
map.m_len = (EXT4_BLOCK_ALIGN(pos + length, blkbits) >> blkbits)
- map.m_lblk;
len = map.m_len;
err = ext4_map_blocks(NULL, inode, &map, 0);
/*
* 'err==len' means that all of blocks has
* been preallocated no matter they are
* initialized or not. For excluding
* unwritten extents, we need to check
* m_flags. There are two conditions that
* indicate for initialized extents. 1) If we
* hit extent cache, EXT4_MAP_MAPPED flag is
* returned; 2) If we do a real lookup,
* non-flags are returned. So we should check
* these two conditions.
*/
if (err == len && (map.m_flags & EXT4_MAP_MAPPED))
overwrite = 1;
}
ret = __generic_file_aio_write(iocb, iov, nr_segs);
mutex_unlock(&inode->i_mutex);
if (ret > 0) {
ssize_t err;
err = generic_write_sync(file, iocb->ki_pos - ret, ret);
if (err < 0)
ret = err;
}
blk_finish_plug(&plug);
if (unaligned_aio)
mutex_unlock(ext4_aio_mutex(inode));
} else {
mutex_lock(&inode->i_mutex);
ret = __generic_file_aio_write(iocb, iov, nr_segs);
mutex_unlock(&inode->i_mutex);
......
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