path: root/fs/attr.c
diff options
authorNeilBrown <neilb@suse.de>2006-01-08 01:02:39 -0800
committerLinus Torvalds <torvalds@g5.osdl.org>2006-01-08 20:13:52 -0800
commit4a30131e7dbb17e5fec6958bfac9da9aff1fa29b (patch)
tree2ff6139b393a9a413e2ea4db4dd2d15eec2201f8 /fs/attr.c
parent788540141f4549637e89aadca6e25cf25eb53383 (diff)
[PATCH] Fix some problems with truncate and mtime semantics.
SUS requires that when truncating a file to the size that it currently is: truncate and ftruncate should NOT modify ctime or mtime O_TRUNC SHOULD modify ctime and mtime. Currently mtime and ctime are always modified on most local filesystems (side effect of ->truncate) or never modified (on NFS). With this patch: ATTR_CTIME|ATTR_MTIME are sent with ATTR_SIZE precisely when an update of these times is required whether size changes or not (via a new argument to do_truncate). This allows NFS to do the right thing for O_TRUNC. inode_setattr nolonger forces ATTR_MTIME|ATTR_CTIME when the ATTR_SIZE sets the size to it's current value. This allows local filesystems to do the right thing for f?truncate. Also, the logic in inode_setattr is changed a bit so there are two return points. One returns the error from vmtruncate if it failed, the other returns 0 (there can be no other failure). Finally, if vmtruncate succeeds, and ATTR_SIZE is the only change requested, we now fall-through and mark_inode_dirty. If a filesystem did not have a ->truncate function, then vmtruncate will have changed i_size, without marking the inode as 'dirty', and I think this is wrong. Signed-off-by: Neil Brown <neilb@suse.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'fs/attr.c')
1 files changed, 8 insertions, 16 deletions
diff --git a/fs/attr.c b/fs/attr.c
index 67bcd9b14ea5..b34732506f1d 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -67,20 +67,12 @@ EXPORT_SYMBOL(inode_change_ok);
int inode_setattr(struct inode * inode, struct iattr * attr)
unsigned int ia_valid = attr->ia_valid;
- int error = 0;
- if (ia_valid & ATTR_SIZE) {
- if (attr->ia_size != i_size_read(inode)) {
- error = vmtruncate(inode, attr->ia_size);
- if (error || (ia_valid == ATTR_SIZE))
- goto out;
- } else {
- /*
- * We skipped the truncate but must still update
- * timestamps
- */
- ia_valid |= ATTR_MTIME|ATTR_CTIME;
- }
+ if (ia_valid & ATTR_SIZE &&
+ attr->ia_size != i_size_read(inode)) {
+ int error = vmtruncate(inode, attr->ia_size);
+ if (error)
+ return error;
if (ia_valid & ATTR_UID)
@@ -104,8 +96,8 @@ int inode_setattr(struct inode * inode, struct iattr * attr)
inode->i_mode = mode;
- return error;
+ return 0;