#include <linux/cdev.h>
#include <linux/fsnotify.h>
#include <linux/sysctl.h>
-#include <linux/lglock.h>
#include <linux/percpu_counter.h>
#include <linux/percpu.h>
#include <linux/hardirq.h>
#include <linux/task_work.h>
#include <linux/ima.h>
+#include <linux/swap.h>
#include <linux/atomic.h>
.max_files = NR_FILE
};
-DEFINE_STATIC_LGLOCK(files_lglock);
-
/* SLAB cache for file structures */
static struct kmem_cache *filp_cachep __read_mostly;
static inline void file_free(struct file *f)
{
percpu_counter_dec(&nr_files);
- file_check_state(f);
call_rcu(&f->f_u.fu_rcuhead, file_free_rcu);
}
* Handle nr_files sysctl
*/
#if defined(CONFIG_SYSCTL) && defined(CONFIG_PROC_FS)
-int proc_nr_files(ctl_table *table, int write,
+int proc_nr_files(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
files_stat.nr_files = get_nr_files();
return proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
}
#else
-int proc_nr_files(ctl_table *table, int write,
+int proc_nr_files(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
return -ENOSYS;
return ERR_PTR(error);
}
- INIT_LIST_HEAD(&f->f_u.fu_list);
atomic_long_set(&f->f_count, 1);
rwlock_init(&f->f_owner.lock);
spin_lock_init(&f->f_lock);
+ mutex_init(&f->f_pos_lock);
eventpoll_init_file(f);
/* f->f_version: 0 */
return f;
/**
* alloc_file - allocate and initialize a 'struct file'
- * @mnt: the vfsmount on which the file will reside
- * @dentry: the dentry representing the new file
+ *
+ * @path: the (dentry, vfsmount) pair for the new file
* @mode: the mode with which the new file will be opened
* @fop: the 'struct file_operations' for the new file
- *
- * Use this instead of get_empty_filp() to get a new
- * 'struct file'. Do so because of the same initialization
- * pitfalls reasons listed for init_file(). This is a
- * preferred interface to using init_file().
- *
- * If all the callers of init_file() are eliminated, its
- * code should be moved into this function.
*/
struct file *alloc_file(struct path *path, fmode_t mode,
const struct file_operations *fop)
file->f_path = *path;
file->f_inode = path->dentry->d_inode;
file->f_mapping = path->dentry->d_inode->i_mapping;
+ if ((mode & FMODE_READ) &&
+ likely(fop->read || fop->read_iter))
+ mode |= FMODE_CAN_READ;
+ if ((mode & FMODE_WRITE) &&
+ likely(fop->write || fop->write_iter))
+ mode |= FMODE_CAN_WRITE;
file->f_mode = mode;
file->f_op = fop;
-
- /*
- * These mounts don't really matter in practice
- * for r/o bind mounts. They aren't userspace-
- * visible. We do this for consistency, and so
- * that we can do debugging checks at __fput()
- */
- if ((mode & FMODE_WRITE) && !special_file(path->dentry->d_inode->i_mode)) {
- file_take_write(file);
- WARN_ON(mnt_clone_write(path->mnt));
- }
if ((mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
i_readcount_inc(path->dentry->d_inode);
return file;
}
EXPORT_SYMBOL(alloc_file);
-/**
- * drop_file_write_access - give up ability to write to a file
- * @file: the file to which we will stop writing
- *
- * This is a central place which will give up the ability
- * to write to @file, along with access to write through
- * its vfsmount.
- */
-static void drop_file_write_access(struct file *file)
-{
- struct vfsmount *mnt = file->f_path.mnt;
- struct dentry *dentry = file->f_path.dentry;
- struct inode *inode = dentry->d_inode;
-
- put_write_access(inode);
-
- if (special_file(inode->i_mode))
- return;
- if (file_check_writeable(file) != 0)
- return;
- __mnt_drop_write(mnt);
- file_release_write(file);
-}
-
/* the real guts of fput() - releasing the last reference to file
*/
static void __fput(struct file *file)
{
struct dentry *dentry = file->f_path.dentry;
struct vfsmount *mnt = file->f_path.mnt;
- struct inode *inode = dentry->d_inode;
+ struct inode *inode = file->f_inode;
might_sleep();
* in the file cleanup chain.
*/
eventpoll_release(file);
- locks_remove_flock(file);
+ locks_remove_file(file);
if (unlikely(file->f_flags & FASYNC)) {
- if (file->f_op && file->f_op->fasync)
+ if (file->f_op->fasync)
file->f_op->fasync(-1, file, 0);
}
ima_file_free(file);
- if (file->f_op && file->f_op->release)
+ if (file->f_op->release)
file->f_op->release(inode, file);
security_file_free(file);
if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL &&
put_pid(file->f_owner.pid);
if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ)
i_readcount_dec(inode);
- if (file->f_mode & FMODE_WRITE)
- drop_file_write_access(file);
+ if (file->f_mode & FMODE_WRITER) {
+ put_write_access(inode);
+ __mnt_drop_write(mnt);
+ }
file->f_path.dentry = NULL;
file->f_path.mnt = NULL;
file->f_inode = NULL;
mntput(mnt);
}
-static DEFINE_SPINLOCK(delayed_fput_lock);
-static LIST_HEAD(delayed_fput_list);
+static LLIST_HEAD(delayed_fput_list);
static void delayed_fput(struct work_struct *unused)
{
- LIST_HEAD(head);
- spin_lock_irq(&delayed_fput_lock);
- list_splice_init(&delayed_fput_list, &head);
- spin_unlock_irq(&delayed_fput_lock);
- while (!list_empty(&head)) {
- struct file *f = list_first_entry(&head, struct file, f_u.fu_list);
- list_del_init(&f->f_u.fu_list);
- __fput(f);
+ struct llist_node *node = llist_del_all(&delayed_fput_list);
+ struct llist_node *next;
+
+ for (; node; node = next) {
+ next = llist_next(node);
+ __fput(llist_entry(node, struct file, f_u.fu_llist));
}
}
delayed_fput(NULL);
}
-static DECLARE_WORK(delayed_fput_work, delayed_fput);
+static DECLARE_DELAYED_WORK(delayed_fput_work, delayed_fput);
void fput(struct file *file)
{
if (atomic_long_dec_and_test(&file->f_count)) {
struct task_struct *task = current;
- unsigned long flags;
- file_sb_list_del(file);
if (likely(!in_interrupt() && !(task->flags & PF_KTHREAD))) {
init_task_work(&file->f_u.fu_rcuhead, ____fput);
if (!task_work_add(task, &file->f_u.fu_rcuhead, true))
return;
+ /*
+ * After this task has run exit_task_work(),
+ * task_work_add() will fail. Fall through to delayed
+ * fput to avoid leaking *file.
+ */
}
- spin_lock_irqsave(&delayed_fput_lock, flags);
- list_add(&file->f_u.fu_list, &delayed_fput_list);
- schedule_work(&delayed_fput_work);
- spin_unlock_irqrestore(&delayed_fput_lock, flags);
+
+ if (llist_add(&file->f_u.fu_llist, &delayed_fput_list))
+ schedule_delayed_work(&delayed_fput_work, 1);
}
}
{
if (atomic_long_dec_and_test(&file->f_count)) {
struct task_struct *task = current;
- file_sb_list_del(file);
BUG_ON(!(task->flags & PF_KTHREAD));
__fput(file);
}
{
if (atomic_long_dec_and_test(&file->f_count)) {
security_file_free(file);
- file_sb_list_del(file);
file_free(file);
}
}
-static inline int file_list_cpu(struct file *file)
-{
-#ifdef CONFIG_SMP
- return file->f_sb_list_cpu;
-#else
- return smp_processor_id();
-#endif
-}
-
-/* helper for file_sb_list_add to reduce ifdefs */
-static inline void __file_sb_list_add(struct file *file, struct super_block *sb)
-{
- struct list_head *list;
-#ifdef CONFIG_SMP
- int cpu;
- cpu = smp_processor_id();
- file->f_sb_list_cpu = cpu;
- list = per_cpu_ptr(sb->s_files, cpu);
-#else
- list = &sb->s_files;
-#endif
- list_add(&file->f_u.fu_list, list);
-}
-
-/**
- * file_sb_list_add - add a file to the sb's file list
- * @file: file to add
- * @sb: sb to add it to
- *
- * Use this function to associate a file with the superblock of the inode it
- * refers to.
- */
-void file_sb_list_add(struct file *file, struct super_block *sb)
-{
- lg_local_lock(&files_lglock);
- __file_sb_list_add(file, sb);
- lg_local_unlock(&files_lglock);
-}
-
-/**
- * file_sb_list_del - remove a file from the sb's file list
- * @file: file to remove
- * @sb: sb to remove it from
- *
- * Use this function to remove a file from its superblock.
- */
-void file_sb_list_del(struct file *file)
-{
- if (!list_empty(&file->f_u.fu_list)) {
- lg_local_lock_cpu(&files_lglock, file_list_cpu(file));
- list_del_init(&file->f_u.fu_list);
- lg_local_unlock_cpu(&files_lglock, file_list_cpu(file));
- }
+void __init files_init(void)
+{
+ filp_cachep = kmem_cache_create("filp", sizeof(struct file), 0,
+ SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL);
+ percpu_counter_init(&nr_files, 0, GFP_KERNEL);
}
-#ifdef CONFIG_SMP
-
/*
- * These macros iterate all files on all CPUs for a given superblock.
- * files_lglock must be held globally.
+ * One file with associated inode and dcache is very roughly 1K. Per default
+ * do not use more than 10% of our memory for files.
*/
-#define do_file_list_for_each_entry(__sb, __file) \
-{ \
- int i; \
- for_each_possible_cpu(i) { \
- struct list_head *list; \
- list = per_cpu_ptr((__sb)->s_files, i); \
- list_for_each_entry((__file), list, f_u.fu_list)
-
-#define while_file_list_for_each_entry \
- } \
-}
-
-#else
-
-#define do_file_list_for_each_entry(__sb, __file) \
-{ \
- struct list_head *list; \
- list = &(sb)->s_files; \
- list_for_each_entry((__file), list, f_u.fu_list)
-
-#define while_file_list_for_each_entry \
-}
-
-#endif
-
-/**
- * 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)
+void __init files_maxfiles_init(void)
{
- struct file *f;
-
- lg_global_lock(&files_lglock);
- do_file_list_for_each_entry(sb, f) {
- if (!S_ISREG(file_inode(f)->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;
- __mnt_drop_write(f->f_path.mnt);
- file_release_write(f);
- } while_file_list_for_each_entry;
- lg_global_unlock(&files_lglock);
-}
-
-void __init files_init(unsigned long mempages)
-{
unsigned long n;
+ unsigned long memreserve = (totalram_pages - nr_free_pages()) * 3/2;
- 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.
- */
+ memreserve = min(memreserve, totalram_pages - 1);
+ n = ((totalram_pages - memreserve) * (PAGE_SIZE / 1024)) / 10;
- n = (mempages * (PAGE_SIZE / 1024)) / 10;
files_stat.max_files = max_t(unsigned long, n, NR_FILE);
- files_defer_init();
- lg_lock_init(&files_lglock, "files_lglock");
- percpu_counter_init(&nr_files, 0);
}
projects / firefly-linux-kernel-4.4.55.git / blobdiff