anonfd: Allow making anon files read-only

It seems a couple places such as arch/ia64/kernel/perfmon.c and
drivers/infiniband/core/uverbs_main.c could use anon_inode_getfile()
instead of a private pseudo-fs + alloc_file(), if only there were a way
to get a read-only file.  So provide this by having anon_inode_getfile()
create a read-only file if we pass O_RDONLY in flags.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Roland Dreier 2009-12-18 09:41:24 -08:00 committed by Al Viro
parent ed2617585f
commit 628ff7c1d8
7 changed files with 17 additions and 9 deletions

View file

@ -4724,7 +4724,7 @@ SYSCALL_DEFINE5(perf_event_open,
if (IS_ERR(event))
goto err_put_context;
err = anon_inode_getfd("[perf_event]", &perf_fops, event, 0);
err = anon_inode_getfd("[perf_event]", &perf_fops, event, O_RDWR);
if (err < 0)
goto err_free_put_context;