#include <linux/fs.h>
#include <linux/security.h>
#include <linux/eventpoll.h>
+#include <linux/rcupdate.h>
#include <linux/mount.h>
#include <linux/cdev.h>
+#include <linux/fsnotify.h>
/* sysctl tunables... */
struct files_stat_struct files_stat = {
spin_unlock_irqrestore(&filp_count_lock, flags);
}
-static inline void file_free(struct file *f)
+static inline void file_free_rcu(struct rcu_head *head)
{
+ struct file *f = container_of(head, struct file, f_rcuhead);
kmem_cache_free(filp_cachep, f);
}
+static inline void file_free(struct file *f)
+{
+ call_rcu(&f->f_rcuhead, file_free_rcu);
+}
+
/* Find an unused file structure and return a pointer to it.
* Returns NULL, if there are no more free file structures or
* we run out of memory.
*/
struct file *get_empty_filp(void)
{
-static int old_max;
+ static int old_max;
struct file * f;
/*
* Privileged users can go above max_files
*/
- if (files_stat.nr_files < files_stat.max_files ||
- capable(CAP_SYS_ADMIN)) {
- f = kmem_cache_alloc(filp_cachep, GFP_KERNEL);
- if (f) {
- memset(f, 0, sizeof(*f));
- if (security_file_alloc(f)) {
- file_free(f);
- goto fail;
- }
- eventpoll_init_file(f);
- atomic_set(&f->f_count, 1);
- f->f_uid = current->fsuid;
- f->f_gid = current->fsgid;
- rwlock_init(&f->f_owner.lock);
- /* f->f_version: 0 */
- INIT_LIST_HEAD(&f->f_list);
- f->f_maxcount = INT_MAX;
- return f;
- }
- }
-
+ if (files_stat.nr_files >= files_stat.max_files &&
+ !capable(CAP_SYS_ADMIN))
+ goto over;
+
+ f = kmem_cache_alloc(filp_cachep, GFP_KERNEL);
+ if (f == NULL)
+ goto fail;
+
+ memset(f, 0, sizeof(*f));
+ if (security_file_alloc(f))
+ goto fail_sec;
+
+ eventpoll_init_file(f);
+ atomic_set(&f->f_count, 1);
+ f->f_uid = current->fsuid;
+ f->f_gid = current->fsgid;
+ rwlock_init(&f->f_owner.lock);
+ /* f->f_version: 0 */
+ INIT_LIST_HEAD(&f->f_list);
+ return f;
+
+over:
/* Ran out of filps - report that */
- if (files_stat.max_files >= old_max) {
+ if (files_stat.nr_files > old_max) {
printk(KERN_INFO "VFS: file-max limit %d reached\n",
files_stat.max_files);
- old_max = files_stat.max_files;
- } else {
- /* Big problems... */
- printk(KERN_WARNING "VFS: filp allocation failed\n");
+ old_max = files_stat.nr_files;
}
+ goto fail;
+
+fail_sec:
+ file_free(f);
fail:
return NULL;
}
void fastcall fput(struct file *file)
{
- if (atomic_dec_and_test(&file->f_count))
+ if (rcuref_dec_and_test(&file->f_count))
__fput(file);
}
struct inode *inode = dentry->d_inode;
might_sleep();
+
+ fsnotify_close(file);
/*
* The function eventpoll_release() should be the first called
* in the file cleanup chain.
struct file *file;
struct files_struct *files = current->files;
- spin_lock(&files->file_lock);
+ rcu_read_lock();
file = fcheck_files(files, fd);
- if (file)
- get_file(file);
- spin_unlock(&files->file_lock);
+ if (file) {
+ if (!rcuref_inc_lf(&file->f_count)) {
+ /* File object ref couldn't be taken */
+ rcu_read_unlock();
+ return NULL;
+ }
+ }
+ rcu_read_unlock();
+
return file;
}
if (likely((atomic_read(&files->count) == 1))) {
file = fcheck_files(files, fd);
} else {
- spin_lock(&files->file_lock);
+ rcu_read_lock();
file = fcheck_files(files, fd);
if (file) {
- get_file(file);
- *fput_needed = 1;
+ if (rcuref_inc_lf(&file->f_count))
+ *fput_needed = 1;
+ else
+ /* Didn't get the reference, someone's freed */
+ file = NULL;
}
- spin_unlock(&files->file_lock);
+ rcu_read_unlock();
}
+
return file;
}
void put_filp(struct file *file)
{
- if (atomic_dec_and_test(&file->f_count)) {
+ if (rcuref_dec_and_test(&file->f_count)) {
security_file_free(file);
file_kill(file);
file_free(file);
files_stat.max_files = n;
if (files_stat.max_files < NR_FILE)
files_stat.max_files = NR_FILE;
+ files_defer_init();
}