From a363f0c2030cb9781e7e458f4a9e354b6c43d7ce Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Tue, 11 Jan 2011 10:13:53 +1100 Subject: [PATCH] xfs: ensure sync write errors are returned xfs_file_aio_write() only returns the error from synchronous flushing of the data and inode if error == 0. At the point where error is being checked, it is guaranteed to be > 0. Therefore any errors returned by the data or fsync flush will never be returned. Fix the checks so we overwrite the current error once and only if an error really occurred. Signed-off-by: Dave Chinner Reviewed-by: Alex Elder Reviewed-by: Christoph Hellwig --- fs/xfs/linux-2.6/xfs_file.c | 49 +++++++++++++++++-------------------- 1 file changed, 23 insertions(+), 26 deletions(-) diff --git a/fs/xfs/linux-2.6/xfs_file.c b/fs/xfs/linux-2.6/xfs_file.c index ba8ad422a165..10b7fb4807a6 100644 --- a/fs/xfs/linux-2.6/xfs_file.c +++ b/fs/xfs/linux-2.6/xfs_file.c @@ -574,7 +574,7 @@ xfs_file_aio_write( struct inode *inode = mapping->host; struct xfs_inode *ip = XFS_I(inode); struct xfs_mount *mp = ip->i_mount; - ssize_t ret = 0, error = 0; + ssize_t ret = 0; int ioflags = 0; xfs_fsize_t isize, new_size; int iolock; @@ -590,9 +590,9 @@ xfs_file_aio_write( if (file->f_mode & FMODE_NOCMTIME) ioflags |= IO_INVIS; - error = generic_segment_checks(iovp, &nr_segs, &ocount, VERIFY_READ); - if (error) - return error; + ret = generic_segment_checks(iovp, &nr_segs, &ocount, VERIFY_READ); + if (ret) + return ret; count = ocount; if (count == 0) @@ -616,9 +616,9 @@ relock: xfs_ilock(ip, XFS_ILOCK_EXCL|iolock); start: - error = -generic_write_checks(file, &pos, &count, + ret = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode)); - if (error) { + if (ret) { xfs_iunlock(ip, XFS_ILOCK_EXCL|iolock); goto out_unlock_mutex; } @@ -660,8 +660,8 @@ start: */ if (pos > ip->i_size) { - error = xfs_zero_eof(ip, pos, ip->i_size); - if (error) { + ret = -xfs_zero_eof(ip, pos, ip->i_size); + if (ret) { xfs_iunlock(ip, XFS_ILOCK_EXCL); goto out_unlock_internal; } @@ -674,8 +674,8 @@ start: * by root. This keeps people from modifying setuid and * setgid binaries. */ - error = -file_remove_suid(file); - if (unlikely(error)) + ret = file_remove_suid(file); + if (unlikely(ret)) goto out_unlock_internal; /* We can write back this queue in page reclaim */ @@ -684,10 +684,10 @@ start: if ((ioflags & IO_ISDIRECT)) { if (mapping->nrpages) { WARN_ON(need_i_mutex == 0); - error = xfs_flushinval_pages(ip, + ret = -xfs_flushinval_pages(ip, (pos & PAGE_CACHE_MASK), -1, FI_REMAPF_LOCKED); - if (error) + if (ret) goto out_unlock_internal; } @@ -720,24 +720,22 @@ start: } } else { int enospc = 0; - ssize_t ret2 = 0; write_retry: trace_xfs_file_buffered_write(ip, count, iocb->ki_pos, ioflags); - ret2 = generic_file_buffered_write(iocb, iovp, nr_segs, + 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 (ret2 == -ENOSPC && !enospc) { - error = xfs_flush_pages(ip, 0, -1, 0, FI_NONE); - if (error) + 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; } - ret = ret2; } current->backing_dev_info = NULL; @@ -753,7 +751,6 @@ write_retry: xfs_iunlock(ip, XFS_ILOCK_EXCL); } - error = -ret; if (ret <= 0) goto out_unlock_internal; @@ -762,23 +759,23 @@ write_retry: /* Handle various SYNC-type writes */ if ((file->f_flags & O_DSYNC) || IS_SYNC(inode)) { loff_t end = pos + ret - 1; - int error2; + int error, error2; xfs_iunlock(ip, iolock); if (need_i_mutex) mutex_unlock(&inode->i_mutex); - error2 = filemap_write_and_wait_range(mapping, pos, end); - if (!error) - error = error2; + error = filemap_write_and_wait_range(mapping, pos, end); if (need_i_mutex) mutex_lock(&inode->i_mutex); xfs_ilock(ip, iolock); error2 = -xfs_file_fsync(file, (file->f_flags & __O_SYNC) ? 0 : 1); - if (!error) - error = error2; + if (error) + ret = error; + else if (error2) + ret = error2; } out_unlock_internal: @@ -800,7 +797,7 @@ write_retry: out_unlock_mutex: if (need_i_mutex) mutex_unlock(&inode->i_mutex); - return -error; + return ret; } STATIC int -- 2.20.1