Kill indirect include of file.h from eventfd.h, use fdget() in cgroup.c

kernel/cgroup.c is the only place in the tree that relies on eventfd.h
pulling file.h; move that include there.  Switch from eventfd_fget()/fput()
to fdget()/fdput(), while we are at it - eventfd_ctx_fileget() will fail
on non-eventfd descriptors just fine, no need to do that check twice...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2013-08-30 12:29:49 -04:00
parent d040790391
commit 4e10f3c988
2 changed files with 19 additions and 17 deletions

View File

@ -9,7 +9,6 @@
#define _LINUX_EVENTFD_H
#include <linux/fcntl.h>
#include <linux/file.h>
#include <linux/wait.h>
/*
@ -26,6 +25,8 @@
#define EFD_SHARED_FCNTL_FLAGS (O_CLOEXEC | O_NONBLOCK)
#define EFD_FLAGS_SET (EFD_SHARED_FCNTL_FLAGS | EFD_SEMAPHORE)
struct file;
#ifdef CONFIG_EVENTFD
struct file *eventfd_file_create(unsigned int count, int flags);

View File

@ -60,6 +60,7 @@
#include <linux/poll.h>
#include <linux/flex_array.h> /* used in cgroup_attach_task */
#include <linux/kthread.h>
#include <linux/file.h>
#include <linux/atomic.h>
@ -4034,8 +4035,8 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *dummy_css,
struct cgroup_event *event;
struct cgroup_subsys_state *cfile_css;
unsigned int efd, cfd;
struct file *efile;
struct file *cfile;
struct fd efile;
struct fd cfile;
char *endp;
int ret;
@ -4058,31 +4059,31 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *dummy_css,
init_waitqueue_func_entry(&event->wait, cgroup_event_wake);
INIT_WORK(&event->remove, cgroup_event_remove);
efile = eventfd_fget(efd);
if (IS_ERR(efile)) {
ret = PTR_ERR(efile);
efile = fdget(efd);
if (!efile.file) {
ret = -EBADF;
goto out_kfree;
}
event->eventfd = eventfd_ctx_fileget(efile);
event->eventfd = eventfd_ctx_fileget(efile.file);
if (IS_ERR(event->eventfd)) {
ret = PTR_ERR(event->eventfd);
goto out_put_efile;
}
cfile = fget(cfd);
if (!cfile) {
cfile = fdget(cfd);
if (!cfile.file) {
ret = -EBADF;
goto out_put_eventfd;
}
/* the process need read permission on control file */
/* AV: shouldn't we check that it's been opened for read instead? */
ret = inode_permission(file_inode(cfile), MAY_READ);
ret = inode_permission(file_inode(cfile.file), MAY_READ);
if (ret < 0)
goto out_put_cfile;
event->cft = __file_cft(cfile);
event->cft = __file_cft(cfile.file);
if (IS_ERR(event->cft)) {
ret = PTR_ERR(event->cft);
goto out_put_cfile;
@ -4103,7 +4104,7 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *dummy_css,
ret = -EINVAL;
event->css = cgroup_css(cgrp, event->cft->ss);
cfile_css = css_from_dir(cfile->f_dentry->d_parent, event->cft->ss);
cfile_css = css_from_dir(cfile.file->f_dentry->d_parent, event->cft->ss);
if (event->css && event->css == cfile_css && css_tryget(event->css))
ret = 0;
@ -4121,25 +4122,25 @@ static int cgroup_write_event_control(struct cgroup_subsys_state *dummy_css,
if (ret)
goto out_put_css;
efile->f_op->poll(efile, &event->pt);
efile.file->f_op->poll(efile.file, &event->pt);
spin_lock(&cgrp->event_list_lock);
list_add(&event->list, &cgrp->event_list);
spin_unlock(&cgrp->event_list_lock);
fput(cfile);
fput(efile);
fdput(cfile);
fdput(efile);
return 0;
out_put_css:
css_put(event->css);
out_put_cfile:
fput(cfile);
fdput(cfile);
out_put_eventfd:
eventfd_ctx_put(event->eventfd);
out_put_efile:
fput(efile);
fdput(efile);
out_kfree:
kfree(event);