cifs: do not ignore the SYNC flags in getattr

Check the AT_STATX_FORCE_SYNC flag and force an attribute
revalidation if requested by the caller, and if the caller
specificies AT_STATX_DONT_SYNC only revalidate cached attributes
if required.  In addition do not flush writes in getattr (which
can be expensive) if size or timestamps not requested by the
caller.

Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Steve French 2020-02-18 18:07:57 -06:00
parent 16fbf79b0f
commit ffdec8d642

View File

@ -2148,8 +2148,9 @@ int cifs_getattr(const struct path *path, struct kstat *stat,
* We need to be sure that all dirty pages are written and the server
* has actual ctime, mtime and file length.
*/
if (!CIFS_CACHE_READ(CIFS_I(inode)) && inode->i_mapping &&
inode->i_mapping->nrpages != 0) {
if ((request_mask & (STATX_CTIME | STATX_MTIME | STATX_SIZE)) &&
!CIFS_CACHE_READ(CIFS_I(inode)) &&
inode->i_mapping && inode->i_mapping->nrpages != 0) {
rc = filemap_fdatawait(inode->i_mapping);
if (rc) {
mapping_set_error(inode->i_mapping, rc);
@ -2157,9 +2158,20 @@ int cifs_getattr(const struct path *path, struct kstat *stat,
}
}
rc = cifs_revalidate_dentry_attr(dentry);
if (rc)
return rc;
if ((flags & AT_STATX_SYNC_TYPE) == AT_STATX_FORCE_SYNC)
CIFS_I(inode)->time = 0; /* force revalidate */
/*
* If the caller doesn't require syncing, only sync if
* necessary (e.g. due to earlier truncate or setattr
* invalidating the cached metadata)
*/
if (((flags & AT_STATX_SYNC_TYPE) != AT_STATX_DONT_SYNC) ||
(CIFS_I(inode)->time == 0)) {
rc = cifs_revalidate_dentry_attr(dentry);
if (rc)
return rc;
}
generic_fillattr(inode, stat);
stat->blksize = cifs_sb->bsize;