From 0f4d634c59a4e062bef81c00d9e63333f2a83b46 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Thu, 26 Mar 2009 13:35:37 -0400 Subject: cifs: flush data on any setattr We already flush all the dirty pages for an inode before doing ATTR_SIZE and ATTR_MTIME changes. There's another problem though -- if we change the mode so that the file becomes read-only then we may not be able to write data to it after a reconnect. Fix this by just going back to flushing all the dirty data on any setattr call. There are probably some cases that can be optimized out, but I'm not sure they're worthwhile and we need to consider them more carefully to make sure that we don't cause regressions if we have to reconnect before writeback occurs. Signed-off-by: Jeff Layton Signed-off-by: Steve French --- fs/cifs/inode.c | 58 +++++++++++++++++++++++++++++---------------------------- 1 file changed, 30 insertions(+), 28 deletions(-) (limited to 'fs/cifs') diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c index f121a80fdd6..89063f1eb55 100644 --- a/fs/cifs/inode.c +++ b/fs/cifs/inode.c @@ -1792,20 +1792,21 @@ cifs_setattr_unix(struct dentry *direntry, struct iattr *attrs) goto out; } - if ((attrs->ia_valid & ATTR_MTIME) || (attrs->ia_valid & ATTR_SIZE)) { - /* - Flush data before changing file size or changing the last - write time of the file on the server. If the - flush returns error, store it to report later and continue. - BB: This should be smarter. Why bother flushing pages that - will be truncated anyway? Also, should we error out here if - the flush returns error? - */ - rc = filemap_write_and_wait(inode->i_mapping); - if (rc != 0) { - cifsInode->write_behind_rc = rc; - rc = 0; - } + /* + * Attempt to flush data before changing attributes. We need to do + * this for ATTR_SIZE and ATTR_MTIME for sure, and if we change the + * ownership or mode then we may also need to do this. Here, we take + * the safe way out and just do the flush on all setattr requests. If + * the flush returns error, store it to report later and continue. + * + * BB: This should be smarter. Why bother flushing pages that + * will be truncated anyway? Also, should we error out here if + * the flush returns error? + */ + rc = filemap_write_and_wait(inode->i_mapping); + if (rc != 0) { + cifsInode->write_behind_rc = rc; + rc = 0; } if (attrs->ia_valid & ATTR_SIZE) { @@ -1903,20 +1904,21 @@ cifs_setattr_nounix(struct dentry *direntry, struct iattr *attrs) return -ENOMEM; } - if ((attrs->ia_valid & ATTR_MTIME) || (attrs->ia_valid & ATTR_SIZE)) { - /* - Flush data before changing file size or changing the last - write time of the file on the server. If the - flush returns error, store it to report later and continue. - BB: This should be smarter. Why bother flushing pages that - will be truncated anyway? Also, should we error out here if - the flush returns error? - */ - rc = filemap_write_and_wait(inode->i_mapping); - if (rc != 0) { - cifsInode->write_behind_rc = rc; - rc = 0; - } + /* + * Attempt to flush data before changing attributes. We need to do + * this for ATTR_SIZE and ATTR_MTIME for sure, and if we change the + * ownership or mode then we may also need to do this. Here, we take + * the safe way out and just do the flush on all setattr requests. If + * the flush returns error, store it to report later and continue. + * + * BB: This should be smarter. Why bother flushing pages that + * will be truncated anyway? Also, should we error out here if + * the flush returns error? + */ + rc = filemap_write_and_wait(inode->i_mapping); + if (rc != 0) { + cifsInode->write_behind_rc = rc; + rc = 0; } if (attrs->ia_valid & ATTR_SIZE) { -- cgit v1.2.3