#include <linux/module.h>
#include <linux/fs.h>
#include <linux/security.h>
-#include <linux/ima.h>
#include <linux/eventpoll.h>
#include <linux/rcupdate.h>
#include <linux/mount.h>
#include <linux/fsnotify.h>
#include <linux/sysctl.h>
#include <linux/percpu_counter.h>
+#include <linux/ima.h>
#include <asm/atomic.h>
+#include "internal.h"
+
/* sysctl tunables... */
struct files_stat_struct files_stat = {
.max_files = NR_FILE
/* public. Not pretty! */
__cacheline_aligned_in_smp DEFINE_SPINLOCK(files_lock);
+/* SLAB cache for file structures */
+static struct kmem_cache *filp_cachep __read_mostly;
+
static struct percpu_counter nr_files __cacheline_aligned_in_smp;
static inline void file_free_rcu(struct rcu_head *head)
* Handle nr_files sysctl
*/
#if defined(CONFIG_SYSCTL) && defined(CONFIG_PROC_FS)
-int proc_nr_files(ctl_table *table, int write, struct file *filp,
+int proc_nr_files(ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
files_stat.nr_files = get_nr_files();
- return proc_dointvec(table, write, filp, buffer, lenp, ppos);
+ return proc_dointvec(table, write, buffer, lenp, ppos);
}
#else
-int proc_nr_files(ctl_table *table, int write, struct file *filp,
+int proc_nr_files(ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
atomic_long_set(&f->f_count, 1);
rwlock_init(&f->f_owner.lock);
f->f_cred = get_cred(cred);
+ spin_lock_init(&f->f_lock);
eventpoll_init_file(f);
/* f->f_version: 0 */
return f;
return NULL;
}
-EXPORT_SYMBOL(get_empty_filp);
-
/**
* alloc_file - allocate and initialize a 'struct file'
* @mnt: the vfsmount on which the file will reside
* If all the callers of init_file() are eliminated, its
* code should be moved into this function.
*/
-struct file *alloc_file(struct vfsmount *mnt, struct dentry *dentry,
- fmode_t mode, const struct file_operations *fop)
+struct file *alloc_file(struct path *path, fmode_t mode,
+ const struct file_operations *fop)
{
struct file *file;
- struct path;
file = get_empty_filp();
if (!file)
return NULL;
- init_file(file, mnt, dentry, mode, fop);
- return file;
-}
-EXPORT_SYMBOL(alloc_file);
-
-/**
- * init_file - initialize a 'struct file'
- * @file: the already allocated 'struct file' to initialized
- * @mnt: the vfsmount on which the file resides
- * @dentry: the dentry representing this file
- * @mode: the mode the file is opened with
- * @fop: the 'struct file_operations' for this file
- *
- * Use this instead of setting the members directly. Doing so
- * avoids making mistakes like forgetting the mntget() or
- * forgetting to take a write on the mnt.
- *
- * Note: This is a crappy interface. It is here to make
- * merging with the existing users of get_empty_filp()
- * who have complex failure logic easier. All users
- * of this should be moving to alloc_file().
- */
-int init_file(struct file *file, struct vfsmount *mnt, struct dentry *dentry,
- fmode_t mode, const struct file_operations *fop)
-{
- int error = 0;
- file->f_path.dentry = dentry;
- file->f_path.mnt = mntget(mnt);
- file->f_mapping = dentry->d_inode->i_mapping;
+ file->f_path = *path;
+ file->f_mapping = path->dentry->d_inode->i_mapping;
file->f_mode = mode;
file->f_op = fop;
* visible. We do this for consistency, and so
* that we can do debugging checks at __fput()
*/
- if ((mode & FMODE_WRITE) && !special_file(dentry->d_inode->i_mode)) {
+ if ((mode & FMODE_WRITE) && !special_file(path->dentry->d_inode->i_mode)) {
file_take_write(file);
- error = mnt_want_write(mnt);
- WARN_ON(error);
+ WARN_ON(mnt_clone_write(path->mnt));
}
- return error;
+ ima_counts_get(file);
+ return file;
}
-EXPORT_SYMBOL(init_file);
+EXPORT_SYMBOL(alloc_file);
void fput(struct file *file)
{
return 0;
}
+/**
+ * mark_files_ro - mark all files read-only
+ * @sb: superblock in question
+ *
+ * All files are marked read-only. We don't care about pending
+ * delete files so this should be used in 'force' mode only.
+ */
+void mark_files_ro(struct super_block *sb)
+{
+ struct file *f;
+
+retry:
+ file_list_lock();
+ list_for_each_entry(f, &sb->s_files, f_u.fu_list) {
+ struct vfsmount *mnt;
+ if (!S_ISREG(f->f_path.dentry->d_inode->i_mode))
+ continue;
+ if (!file_count(f))
+ continue;
+ if (!(f->f_mode & FMODE_WRITE))
+ continue;
+ spin_lock(&f->f_lock);
+ f->f_mode &= ~FMODE_WRITE;
+ spin_unlock(&f->f_lock);
+ if (file_check_writeable(f) != 0)
+ continue;
+ file_release_write(f);
+ mnt = mntget(f->f_path.mnt);
+ file_list_unlock();
+ /*
+ * This can sleep, so we can't hold
+ * the file_list_lock() spinlock.
+ */
+ mnt_drop_write(mnt);
+ mntput(mnt);
+ goto retry;
+ }
+ file_list_unlock();
+}
+
void __init files_init(unsigned long mempages)
{
int n;
- /* One file with associated inode and dcache is very roughly 1K.
+
+ filp_cachep = kmem_cache_create("filp", sizeof(struct file), 0,
+ SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL);
+
+ /*
+ * One file with associated inode and dcache is very roughly 1K.
* Per default don't use more than 10% of our memory for files.
*/
Code Review / linux-2.6.git / blobdiff