IMO sys_readahead() doesn't make sense if the file is opened with
O_DIRECT, because the page cache is stuffed but never used. Therefore
this patch changes that by letting the call return with -EINVAL.
Signed-off-by: Jan Blunck <[EMAIL PROTECTED]>
mm/filemap.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletion(-)
Index: experimental-jb/mm/filemap.c
===================================================================
--- experimental-jb.orig/mm/filemap.c
+++ experimental-jb/mm/filemap.c
@@ -1111,7 +1111,8 @@ static ssize_t
do_readahead(struct address_space *mapping, struct file *filp,
unsigned long index, unsigned long nr)
{
- if (!mapping || !mapping->a_ops || !mapping->a_ops->readpage)
+ if (!mapping || !mapping->a_ops || !mapping->a_ops->readpage
+ || (filp->f_flags & O_DIRECT))
return -EINVAL;
force_page_cache_readahead(mapping, filp, index,
