From 4d8d15812fd9bc96d0da11467d23e0373feae933 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Tue, 11 Jan 2011 10:23:42 +1100 Subject: [PATCH] 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: Dave Chinner Reviewed-by: Alex Elder Reviewed-by: Christoph Hellwig --- fs/xfs/linux-2.6/xfs_file.c | 123 ++++++++++++++++-------------------- 1 file changed, 56 insertions(+), 67 deletions(-) diff --git a/fs/xfs/linux-2.6/xfs_file.c b/fs/xfs/linux-2.6/xfs_file.c index e2bcf51d292..5863dd8f448 100644 --- a/fs/xfs/linux-2.6/xfs_file.c +++ b/fs/xfs/linux-2.6/xfs_file.c @@ -628,6 +628,58 @@ out_lock: 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 */ -- 2.39.5