提交 4d8d1581 编写于 作者: D Dave Chinner 提交者: Dave Chinner

xfs: factor common write setup code

The buffered IO and direct IO write paths share a common set of
checks and limiting code prior to issuing the write. Factor that
into a common helper function.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NAlex Elder <aelder@sgi.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
上级 637bbc75
......@@ -628,6 +628,58 @@ xfs_zero_eof(
return error;
}
/*
* Common pre-write limit and setup checks.
*
* Returns with iolock held according to @iolock.
*/
STATIC ssize_t
xfs_file_aio_write_checks(
struct file *file,
loff_t *pos,
size_t *count,
int *iolock)
{
struct inode *inode = file->f_mapping->host;
struct xfs_inode *ip = XFS_I(inode);
xfs_fsize_t new_size;
int error = 0;
error = generic_write_checks(file, pos, count, S_ISBLK(inode->i_mode));
if (error) {
xfs_rw_iunlock(ip, XFS_ILOCK_EXCL | *iolock);
*iolock = 0;
return error;
}
new_size = *pos + *count;
if (new_size > ip->i_size)
ip->i_new_size = new_size;
if (likely(!(file->f_mode & FMODE_NOCMTIME)))
file_update_time(file);
/*
* If the offset is beyond the size of the file, we need to zero any
* blocks that fall between the existing EOF and the start of this
* write.
*/
if (*pos > ip->i_size)
error = -xfs_zero_eof(ip, *pos, ip->i_size);
xfs_rw_iunlock(ip, XFS_ILOCK_EXCL);
if (error)
return error;
/*
* If we're writing the file then make sure to clear the setuid and
* setgid bits if the process is not being run by root. This keeps
* people from modifying setuid and setgid binaries.
*/
return file_remove_suid(file);
}
/*
* xfs_file_dio_aio_write - handle direct IO writes
*
......@@ -653,7 +705,6 @@ xfs_file_dio_aio_write(
struct xfs_inode *ip = XFS_I(inode);
struct xfs_mount *mp = ip->i_mount;
ssize_t ret = 0;
xfs_fsize_t new_size;
size_t count = ocount;
struct xfs_buftarg *target = XFS_IS_REALTIME_INODE(ip) ?
mp->m_rtdev_targp : mp->m_ddev_targp;
......@@ -674,45 +725,8 @@ xfs_file_dio_aio_write(
*iolock = XFS_IOLOCK_SHARED;
xfs_rw_ilock(ip, XFS_ILOCK_EXCL | *iolock);
ret = generic_write_checks(file, &pos, &count,
S_ISBLK(inode->i_mode));
if (ret) {
xfs_rw_iunlock(ip, XFS_ILOCK_EXCL | *iolock);
*iolock = 0;
return ret;
}
new_size = pos + count;
if (new_size > ip->i_size)
ip->i_new_size = new_size;
if (likely(!(file->f_mode & FMODE_NOCMTIME)))
file_update_time(file);
/*
* If the offset is beyond the size of the file, we have a couple of
* things to do. First, if there is already space allocated we need to
* either create holes or zero the disk or ...
*
* If there is a page where the previous size lands, we need to zero it
* out up to the new size.
*/
if (pos > ip->i_size) {
ret = -xfs_zero_eof(ip, pos, ip->i_size);
if (ret) {
xfs_rw_iunlock(ip, XFS_ILOCK_EXCL);
return ret;
}
}
xfs_rw_iunlock(ip, XFS_ILOCK_EXCL);
/*
* If we're writing the file then make sure to clear the setuid and
* setgid bits if the process is not being run by root. This keeps
* people from modifying setuid and setgid binaries.
*/
ret = file_remove_suid(file);
if (unlikely(ret))
ret = xfs_file_aio_write_checks(file, &pos, &count, iolock);
if (ret)
return ret;
if (mapping->nrpages) {
......@@ -753,38 +767,13 @@ xfs_file_buffered_aio_write(
struct xfs_inode *ip = XFS_I(inode);
ssize_t ret;
int enospc = 0;
xfs_fsize_t new_size;
size_t count = ocount;
*iolock = XFS_IOLOCK_EXCL;
xfs_rw_ilock(ip, XFS_ILOCK_EXCL | *iolock);
ret = generic_write_checks(file, &pos, &count,
S_ISBLK(inode->i_mode));
if (ret) {
xfs_rw_iunlock(ip, XFS_ILOCK_EXCL | *iolock);
*iolock = 0;
return ret;
}
new_size = pos + count;
if (new_size > ip->i_size)
ip->i_new_size = new_size;
if (likely(!(file->f_mode & FMODE_NOCMTIME)))
file_update_time(file);
if (pos > ip->i_size) {
ret = -xfs_zero_eof(ip, pos, ip->i_size);
if (ret) {
xfs_rw_iunlock(ip, XFS_ILOCK_EXCL);
return ret;
}
}
xfs_rw_iunlock(ip, XFS_ILOCK_EXCL);
ret = file_remove_suid(file);
if (unlikely(ret))
ret = xfs_file_aio_write_checks(file, &pos, &count, iolock);
if (ret)
return ret;
/* We can write back this queue in page reclaim */
......
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册