From 637bbc75d9fda57c7bc77ce5ee37e29a77a0520d Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Tue, 11 Jan 2011 10:17:30 +1100 Subject: [PATCH] xfs: split buffered IO write path from xfs_file_aio_write Complete the split of the different write IO paths by splitting the buffered IO write path out of xfs_file_aio_write(). This makes the different mechanisms of the write patchs easier to follow. Signed-off-by: Dave Chinner Reviewed-by: Alex Elder Reviewed-by: Christoph Hellwig --- fs/xfs/linux-2.6/xfs_file.c | 146 +++++++++++++++++------------------- 1 file changed, 69 insertions(+), 77 deletions(-) diff --git a/fs/xfs/linux-2.6/xfs_file.c b/fs/xfs/linux-2.6/xfs_file.c index 00661fd21fc0..e2bcf51d292e 100644 --- a/fs/xfs/linux-2.6/xfs_file.c +++ b/fs/xfs/linux-2.6/xfs_file.c @@ -739,58 +739,31 @@ xfs_file_dio_aio_write( } STATIC ssize_t -xfs_file_aio_write( +xfs_file_buffered_aio_write( struct kiocb *iocb, const struct iovec *iovp, unsigned long nr_segs, - loff_t pos) + loff_t pos, + size_t ocount, + int *iolock) { struct file *file = iocb->ki_filp; struct address_space *mapping = file->f_mapping; struct inode *inode = mapping->host; struct xfs_inode *ip = XFS_I(inode); - struct xfs_mount *mp = ip->i_mount; - ssize_t ret = 0; - int ioflags = 0; + ssize_t ret; + int enospc = 0; xfs_fsize_t new_size; - int iolock; - size_t ocount = 0, count; - - XFS_STATS_INC(xs_write_calls); - - BUG_ON(iocb->ki_pos != pos); - - if (unlikely(file->f_flags & O_DIRECT)) - ioflags |= IO_ISDIRECT; - if (file->f_mode & FMODE_NOCMTIME) - ioflags |= IO_INVIS; - - ret = generic_segment_checks(iovp, &nr_segs, &ocount, VERIFY_READ); - if (ret) - return ret; - - count = ocount; - if (count == 0) - return 0; - - xfs_wait_for_freeze(mp, SB_FREEZE_WRITE); - - if (XFS_FORCED_SHUTDOWN(mp)) - return -EIO; + size_t count = ocount; -relock: - if (ioflags & IO_ISDIRECT) { - ret = xfs_file_dio_aio_write(iocb, iovp, nr_segs, pos, - ocount, &iolock); - goto done_io; - } - iolock = XFS_IOLOCK_EXCL; + *iolock = XFS_IOLOCK_EXCL; + xfs_rw_ilock(ip, XFS_ILOCK_EXCL | *iolock); - 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); + xfs_rw_iunlock(ip, XFS_ILOCK_EXCL | *iolock); + *iolock = 0; return ret; } @@ -798,67 +771,86 @@ relock: if (new_size > ip->i_size) ip->i_new_size = new_size; - if (likely(!(ioflags & IO_INVIS))) + 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); - goto out_unlock_internal; + 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)) - goto out_unlock_internal; + return ret; /* We can write back this queue in page reclaim */ current->backing_dev_info = mapping->backing_dev_info; - if (!(ioflags & IO_ISDIRECT)) { - int enospc = 0; - write_retry: - trace_xfs_file_buffered_write(ip, count, iocb->ki_pos, ioflags); - ret = generic_file_buffered_write(iocb, iovp, nr_segs, - pos, &iocb->ki_pos, count, ret); - /* - * if we just got an ENOSPC, flush the inode now we - * aren't holding any page locks and retry *once* - */ - if (ret == -ENOSPC && !enospc) { - ret = xfs_flush_pages(ip, 0, -1, 0, FI_NONE); - if (ret) - goto out_unlock_internal; - enospc = 1; - goto write_retry; - } + trace_xfs_file_buffered_write(ip, count, iocb->ki_pos, 0); + ret = generic_file_buffered_write(iocb, iovp, nr_segs, + pos, &iocb->ki_pos, count, ret); + /* + * if we just got an ENOSPC, flush the inode now we aren't holding any + * page locks and retry *once* + */ + if (ret == -ENOSPC && !enospc) { + ret = -xfs_flush_pages(ip, 0, -1, 0, FI_NONE); + if (ret) + return ret; + enospc = 1; + goto write_retry; } - current->backing_dev_info = NULL; + return ret; +} + +STATIC ssize_t +xfs_file_aio_write( + struct kiocb *iocb, + const struct iovec *iovp, + unsigned long nr_segs, + loff_t pos) +{ + struct file *file = iocb->ki_filp; + struct address_space *mapping = file->f_mapping; + struct inode *inode = mapping->host; + struct xfs_inode *ip = XFS_I(inode); + ssize_t ret; + int iolock; + size_t ocount = 0; + + XFS_STATS_INC(xs_write_calls); + + BUG_ON(iocb->ki_pos != pos); + + ret = generic_segment_checks(iovp, &nr_segs, &ocount, VERIFY_READ); + if (ret) + return ret; + + if (ocount == 0) + return 0; + + xfs_wait_for_freeze(ip->i_mount, SB_FREEZE_WRITE); + + if (XFS_FORCED_SHUTDOWN(ip->i_mount)) + return -EIO; + + if (unlikely(file->f_flags & O_DIRECT)) + ret = xfs_file_dio_aio_write(iocb, iovp, nr_segs, pos, + ocount, &iolock); + else + ret = xfs_file_buffered_aio_write(iocb, iovp, nr_segs, pos, + ocount, &iolock); -done_io: xfs_aio_write_isize_update(inode, &iocb->ki_pos, ret); if (ret <= 0) - goto out_unlock_internal; + goto out_unlock; /* Handle various SYNC-type writes */ if ((file->f_flags & O_DSYNC) || IS_SYNC(inode)) { @@ -877,7 +869,7 @@ done_io: ret = error2; } - out_unlock_internal: +out_unlock: xfs_aio_write_newsize_update(ip); xfs_rw_iunlock(ip, iolock); return ret; -- 2.39.5