mirror of
https://github.com/AetherDroid/android_kernel_samsung_on5xelte.git
synced 2025-09-08 01:08:03 -04:00
Fixed MTP to work with TWRP
This commit is contained in:
awab228
commit
f6dfaef42e
50820 changed files with 20846062 additions and 0 deletions
758
fs/fcntl.c
Normal file
758
fs/fcntl.c
Normal file
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@ -0,0 +1,758 @@
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/*
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* linux/fs/fcntl.c
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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*/
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#include <linux/syscalls.h>
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#include <linux/init.h>
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#include <linux/mm.h>
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#include <linux/fs.h>
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#include <linux/file.h>
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#include <linux/fdtable.h>
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#include <linux/capability.h>
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#include <linux/dnotify.h>
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#include <linux/slab.h>
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#include <linux/module.h>
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#include <linux/pipe_fs_i.h>
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#include <linux/security.h>
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#include <linux/ptrace.h>
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#include <linux/signal.h>
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#include <linux/rcupdate.h>
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#include <linux/pid_namespace.h>
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#include <linux/user_namespace.h>
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#include <linux/shmem_fs.h>
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#include <asm/poll.h>
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#include <asm/siginfo.h>
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#include <asm/uaccess.h>
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#define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | O_DIRECT | O_NOATIME)
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static int setfl(int fd, struct file * filp, unsigned long arg)
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{
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struct inode * inode = file_inode(filp);
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int error = 0;
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/*
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* O_APPEND cannot be cleared if the file is marked as append-only
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* and the file is open for write.
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*/
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if (((arg ^ filp->f_flags) & O_APPEND) && IS_APPEND(inode))
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return -EPERM;
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/* O_NOATIME can only be set by the owner or superuser */
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if ((arg & O_NOATIME) && !(filp->f_flags & O_NOATIME))
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if (!inode_owner_or_capable(inode))
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return -EPERM;
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/* required for strict SunOS emulation */
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if (O_NONBLOCK != O_NDELAY)
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if (arg & O_NDELAY)
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arg |= O_NONBLOCK;
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if (arg & O_DIRECT) {
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if (!filp->f_mapping || !filp->f_mapping->a_ops ||
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!filp->f_mapping->a_ops->direct_IO)
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return -EINVAL;
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}
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if (filp->f_op->check_flags)
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error = filp->f_op->check_flags(arg);
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if (error)
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return error;
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/*
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* ->fasync() is responsible for setting the FASYNC bit.
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*/
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if (((arg ^ filp->f_flags) & FASYNC) && filp->f_op->fasync) {
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error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0);
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if (error < 0)
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goto out;
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if (error > 0)
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error = 0;
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}
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spin_lock(&filp->f_lock);
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filp->f_flags = (arg & SETFL_MASK) | (filp->f_flags & ~SETFL_MASK);
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spin_unlock(&filp->f_lock);
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out:
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return error;
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}
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static void f_modown(struct file *filp, struct pid *pid, enum pid_type type,
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int force)
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{
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write_lock_irq(&filp->f_owner.lock);
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if (force || !filp->f_owner.pid) {
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put_pid(filp->f_owner.pid);
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filp->f_owner.pid = get_pid(pid);
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filp->f_owner.pid_type = type;
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if (pid) {
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const struct cred *cred = current_cred();
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filp->f_owner.uid = cred->uid;
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filp->f_owner.euid = cred->euid;
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}
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}
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write_unlock_irq(&filp->f_owner.lock);
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}
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void __f_setown(struct file *filp, struct pid *pid, enum pid_type type,
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int force)
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{
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security_file_set_fowner(filp);
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f_modown(filp, pid, type, force);
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}
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EXPORT_SYMBOL(__f_setown);
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void f_setown(struct file *filp, unsigned long arg, int force)
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{
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enum pid_type type;
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struct pid *pid;
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int who = arg;
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type = PIDTYPE_PID;
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if (who < 0) {
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type = PIDTYPE_PGID;
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who = -who;
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}
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rcu_read_lock();
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pid = find_vpid(who);
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__f_setown(filp, pid, type, force);
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rcu_read_unlock();
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}
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EXPORT_SYMBOL(f_setown);
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void f_delown(struct file *filp)
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{
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f_modown(filp, NULL, PIDTYPE_PID, 1);
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}
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pid_t f_getown(struct file *filp)
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{
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pid_t pid;
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read_lock(&filp->f_owner.lock);
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pid = pid_vnr(filp->f_owner.pid);
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if (filp->f_owner.pid_type == PIDTYPE_PGID)
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pid = -pid;
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read_unlock(&filp->f_owner.lock);
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return pid;
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}
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static int f_setown_ex(struct file *filp, unsigned long arg)
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{
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struct f_owner_ex __user *owner_p = (void __user *)arg;
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struct f_owner_ex owner;
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struct pid *pid;
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int type;
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int ret;
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ret = copy_from_user(&owner, owner_p, sizeof(owner));
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if (ret)
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return -EFAULT;
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switch (owner.type) {
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case F_OWNER_TID:
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type = PIDTYPE_MAX;
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break;
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case F_OWNER_PID:
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type = PIDTYPE_PID;
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break;
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case F_OWNER_PGRP:
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type = PIDTYPE_PGID;
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break;
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default:
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return -EINVAL;
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}
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rcu_read_lock();
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pid = find_vpid(owner.pid);
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if (owner.pid && !pid)
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ret = -ESRCH;
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else
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__f_setown(filp, pid, type, 1);
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rcu_read_unlock();
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return ret;
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}
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static int f_getown_ex(struct file *filp, unsigned long arg)
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{
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struct f_owner_ex __user *owner_p = (void __user *)arg;
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struct f_owner_ex owner;
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int ret = 0;
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read_lock(&filp->f_owner.lock);
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owner.pid = pid_vnr(filp->f_owner.pid);
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switch (filp->f_owner.pid_type) {
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case PIDTYPE_MAX:
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owner.type = F_OWNER_TID;
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break;
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case PIDTYPE_PID:
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owner.type = F_OWNER_PID;
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break;
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case PIDTYPE_PGID:
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owner.type = F_OWNER_PGRP;
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break;
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default:
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WARN_ON(1);
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ret = -EINVAL;
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break;
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}
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read_unlock(&filp->f_owner.lock);
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if (!ret) {
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ret = copy_to_user(owner_p, &owner, sizeof(owner));
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if (ret)
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ret = -EFAULT;
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}
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return ret;
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}
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#ifdef CONFIG_CHECKPOINT_RESTORE
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static int f_getowner_uids(struct file *filp, unsigned long arg)
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{
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struct user_namespace *user_ns = current_user_ns();
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uid_t __user *dst = (void __user *)arg;
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uid_t src[2];
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int err;
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read_lock(&filp->f_owner.lock);
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src[0] = from_kuid(user_ns, filp->f_owner.uid);
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src[1] = from_kuid(user_ns, filp->f_owner.euid);
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read_unlock(&filp->f_owner.lock);
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err = put_user(src[0], &dst[0]);
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err |= put_user(src[1], &dst[1]);
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return err;
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}
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#else
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static int f_getowner_uids(struct file *filp, unsigned long arg)
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{
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return -EINVAL;
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}
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#endif
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static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
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struct file *filp)
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{
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long err = -EINVAL;
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switch (cmd) {
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case F_DUPFD:
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err = f_dupfd(arg, filp, 0);
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break;
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case F_DUPFD_CLOEXEC:
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err = f_dupfd(arg, filp, O_CLOEXEC);
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break;
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case F_GETFD:
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err = get_close_on_exec(fd) ? FD_CLOEXEC : 0;
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break;
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case F_SETFD:
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err = 0;
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set_close_on_exec(fd, arg & FD_CLOEXEC);
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break;
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case F_GETFL:
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err = filp->f_flags;
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break;
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case F_SETFL:
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err = setfl(fd, filp, arg);
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break;
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#if BITS_PER_LONG != 32
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/* 32-bit arches must use fcntl64() */
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case F_OFD_GETLK:
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#endif
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case F_GETLK:
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err = fcntl_getlk(filp, cmd, (struct flock __user *) arg);
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break;
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#if BITS_PER_LONG != 32
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/* 32-bit arches must use fcntl64() */
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case F_OFD_SETLK:
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case F_OFD_SETLKW:
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#endif
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/* Fallthrough */
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case F_SETLK:
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case F_SETLKW:
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err = fcntl_setlk(fd, filp, cmd, (struct flock __user *) arg);
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break;
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case F_GETOWN:
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/*
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* XXX If f_owner is a process group, the
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* negative return value will get converted
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* into an error. Oops. If we keep the
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* current syscall conventions, the only way
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* to fix this will be in libc.
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*/
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err = f_getown(filp);
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force_successful_syscall_return();
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break;
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||||
case F_SETOWN:
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f_setown(filp, arg, 1);
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err = 0;
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||||
break;
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||||
case F_GETOWN_EX:
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||||
err = f_getown_ex(filp, arg);
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break;
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||||
case F_SETOWN_EX:
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||||
err = f_setown_ex(filp, arg);
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||||
break;
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||||
case F_GETOWNER_UIDS:
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||||
err = f_getowner_uids(filp, arg);
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||||
break;
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||||
case F_GETSIG:
|
||||
err = filp->f_owner.signum;
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||||
break;
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||||
case F_SETSIG:
|
||||
/* arg == 0 restores default behaviour. */
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||||
if (!valid_signal(arg)) {
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||||
break;
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||||
}
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||||
err = 0;
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||||
filp->f_owner.signum = arg;
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||||
break;
|
||||
case F_GETLEASE:
|
||||
err = fcntl_getlease(filp);
|
||||
break;
|
||||
case F_SETLEASE:
|
||||
err = fcntl_setlease(fd, filp, arg);
|
||||
break;
|
||||
case F_NOTIFY:
|
||||
err = fcntl_dirnotify(fd, filp, arg);
|
||||
break;
|
||||
case F_SETPIPE_SZ:
|
||||
case F_GETPIPE_SZ:
|
||||
err = pipe_fcntl(filp, cmd, arg);
|
||||
break;
|
||||
case F_ADD_SEALS:
|
||||
case F_GET_SEALS:
|
||||
err = shmem_fcntl(filp, cmd, arg);
|
||||
break;
|
||||
default:
|
||||
break;
|
||||
}
|
||||
return err;
|
||||
}
|
||||
|
||||
static int check_fcntl_cmd(unsigned cmd)
|
||||
{
|
||||
switch (cmd) {
|
||||
case F_DUPFD:
|
||||
case F_DUPFD_CLOEXEC:
|
||||
case F_GETFD:
|
||||
case F_SETFD:
|
||||
case F_GETFL:
|
||||
return 1;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
SYSCALL_DEFINE3(fcntl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
|
||||
{
|
||||
struct fd f = fdget_raw(fd);
|
||||
long err = -EBADF;
|
||||
|
||||
if (!f.file)
|
||||
goto out;
|
||||
|
||||
if (unlikely(f.file->f_mode & FMODE_PATH)) {
|
||||
if (!check_fcntl_cmd(cmd))
|
||||
goto out1;
|
||||
}
|
||||
|
||||
err = security_file_fcntl(f.file, cmd, arg);
|
||||
if (!err)
|
||||
err = do_fcntl(fd, cmd, arg, f.file);
|
||||
|
||||
out1:
|
||||
fdput(f);
|
||||
out:
|
||||
return err;
|
||||
}
|
||||
|
||||
#if BITS_PER_LONG == 32
|
||||
SYSCALL_DEFINE3(fcntl64, unsigned int, fd, unsigned int, cmd,
|
||||
unsigned long, arg)
|
||||
{
|
||||
struct fd f = fdget_raw(fd);
|
||||
long err = -EBADF;
|
||||
|
||||
if (!f.file)
|
||||
goto out;
|
||||
|
||||
if (unlikely(f.file->f_mode & FMODE_PATH)) {
|
||||
if (!check_fcntl_cmd(cmd))
|
||||
goto out1;
|
||||
}
|
||||
|
||||
err = security_file_fcntl(f.file, cmd, arg);
|
||||
if (err)
|
||||
goto out1;
|
||||
|
||||
switch (cmd) {
|
||||
case F_GETLK64:
|
||||
case F_OFD_GETLK:
|
||||
err = fcntl_getlk64(f.file, cmd, (struct flock64 __user *) arg);
|
||||
break;
|
||||
case F_SETLK64:
|
||||
case F_SETLKW64:
|
||||
case F_OFD_SETLK:
|
||||
case F_OFD_SETLKW:
|
||||
err = fcntl_setlk64(fd, f.file, cmd,
|
||||
(struct flock64 __user *) arg);
|
||||
break;
|
||||
default:
|
||||
err = do_fcntl(fd, cmd, arg, f.file);
|
||||
break;
|
||||
}
|
||||
out1:
|
||||
fdput(f);
|
||||
out:
|
||||
return err;
|
||||
}
|
||||
#endif
|
||||
|
||||
/* Table to convert sigio signal codes into poll band bitmaps */
|
||||
|
||||
static const long band_table[NSIGPOLL] = {
|
||||
POLLIN | POLLRDNORM, /* POLL_IN */
|
||||
POLLOUT | POLLWRNORM | POLLWRBAND, /* POLL_OUT */
|
||||
POLLIN | POLLRDNORM | POLLMSG, /* POLL_MSG */
|
||||
POLLERR, /* POLL_ERR */
|
||||
POLLPRI | POLLRDBAND, /* POLL_PRI */
|
||||
POLLHUP | POLLERR /* POLL_HUP */
|
||||
};
|
||||
|
||||
static inline int sigio_perm(struct task_struct *p,
|
||||
struct fown_struct *fown, int sig)
|
||||
{
|
||||
const struct cred *cred;
|
||||
int ret;
|
||||
|
||||
rcu_read_lock();
|
||||
cred = __task_cred(p);
|
||||
ret = ((uid_eq(fown->euid, GLOBAL_ROOT_UID) ||
|
||||
uid_eq(fown->euid, cred->suid) || uid_eq(fown->euid, cred->uid) ||
|
||||
uid_eq(fown->uid, cred->suid) || uid_eq(fown->uid, cred->uid)) &&
|
||||
!security_file_send_sigiotask(p, fown, sig));
|
||||
rcu_read_unlock();
|
||||
return ret;
|
||||
}
|
||||
|
||||
static void send_sigio_to_task(struct task_struct *p,
|
||||
struct fown_struct *fown,
|
||||
int fd, int reason, int group)
|
||||
{
|
||||
/*
|
||||
* F_SETSIG can change ->signum lockless in parallel, make
|
||||
* sure we read it once and use the same value throughout.
|
||||
*/
|
||||
int signum = ACCESS_ONCE(fown->signum);
|
||||
|
||||
if (!sigio_perm(p, fown, signum))
|
||||
return;
|
||||
|
||||
switch (signum) {
|
||||
siginfo_t si;
|
||||
default:
|
||||
/* Queue a rt signal with the appropriate fd as its
|
||||
value. We use SI_SIGIO as the source, not
|
||||
SI_KERNEL, since kernel signals always get
|
||||
delivered even if we can't queue. Failure to
|
||||
queue in this case _should_ be reported; we fall
|
||||
back to SIGIO in that case. --sct */
|
||||
si.si_signo = signum;
|
||||
si.si_errno = 0;
|
||||
si.si_code = reason;
|
||||
/* Make sure we are called with one of the POLL_*
|
||||
reasons, otherwise we could leak kernel stack into
|
||||
userspace. */
|
||||
BUG_ON((reason & __SI_MASK) != __SI_POLL);
|
||||
if (reason - POLL_IN >= NSIGPOLL)
|
||||
si.si_band = ~0L;
|
||||
else
|
||||
si.si_band = band_table[reason - POLL_IN];
|
||||
si.si_fd = fd;
|
||||
if (!do_send_sig_info(signum, &si, p, group))
|
||||
break;
|
||||
/* fall-through: fall back on the old plain SIGIO signal */
|
||||
case 0:
|
||||
do_send_sig_info(SIGIO, SEND_SIG_PRIV, p, group);
|
||||
}
|
||||
}
|
||||
|
||||
void send_sigio(struct fown_struct *fown, int fd, int band)
|
||||
{
|
||||
struct task_struct *p;
|
||||
enum pid_type type;
|
||||
struct pid *pid;
|
||||
int group = 1;
|
||||
|
||||
read_lock(&fown->lock);
|
||||
|
||||
type = fown->pid_type;
|
||||
if (type == PIDTYPE_MAX) {
|
||||
group = 0;
|
||||
type = PIDTYPE_PID;
|
||||
}
|
||||
|
||||
pid = fown->pid;
|
||||
if (!pid)
|
||||
goto out_unlock_fown;
|
||||
|
||||
read_lock(&tasklist_lock);
|
||||
do_each_pid_task(pid, type, p) {
|
||||
send_sigio_to_task(p, fown, fd, band, group);
|
||||
} while_each_pid_task(pid, type, p);
|
||||
read_unlock(&tasklist_lock);
|
||||
out_unlock_fown:
|
||||
read_unlock(&fown->lock);
|
||||
}
|
||||
|
||||
static void send_sigurg_to_task(struct task_struct *p,
|
||||
struct fown_struct *fown, int group)
|
||||
{
|
||||
if (sigio_perm(p, fown, SIGURG))
|
||||
do_send_sig_info(SIGURG, SEND_SIG_PRIV, p, group);
|
||||
}
|
||||
|
||||
int send_sigurg(struct fown_struct *fown)
|
||||
{
|
||||
struct task_struct *p;
|
||||
enum pid_type type;
|
||||
struct pid *pid;
|
||||
int group = 1;
|
||||
int ret = 0;
|
||||
|
||||
read_lock(&fown->lock);
|
||||
|
||||
type = fown->pid_type;
|
||||
if (type == PIDTYPE_MAX) {
|
||||
group = 0;
|
||||
type = PIDTYPE_PID;
|
||||
}
|
||||
|
||||
pid = fown->pid;
|
||||
if (!pid)
|
||||
goto out_unlock_fown;
|
||||
|
||||
ret = 1;
|
||||
|
||||
read_lock(&tasklist_lock);
|
||||
do_each_pid_task(pid, type, p) {
|
||||
send_sigurg_to_task(p, fown, group);
|
||||
} while_each_pid_task(pid, type, p);
|
||||
read_unlock(&tasklist_lock);
|
||||
out_unlock_fown:
|
||||
read_unlock(&fown->lock);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static DEFINE_SPINLOCK(fasync_lock);
|
||||
static struct kmem_cache *fasync_cache __read_mostly;
|
||||
|
||||
static void fasync_free_rcu(struct rcu_head *head)
|
||||
{
|
||||
kmem_cache_free(fasync_cache,
|
||||
container_of(head, struct fasync_struct, fa_rcu));
|
||||
}
|
||||
|
||||
/*
|
||||
* Remove a fasync entry. If successfully removed, return
|
||||
* positive and clear the FASYNC flag. If no entry exists,
|
||||
* do nothing and return 0.
|
||||
*
|
||||
* NOTE! It is very important that the FASYNC flag always
|
||||
* match the state "is the filp on a fasync list".
|
||||
*
|
||||
*/
|
||||
int fasync_remove_entry(struct file *filp, struct fasync_struct **fapp)
|
||||
{
|
||||
struct fasync_struct *fa, **fp;
|
||||
int result = 0;
|
||||
|
||||
spin_lock(&filp->f_lock);
|
||||
spin_lock(&fasync_lock);
|
||||
for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
|
||||
if (fa->fa_file != filp)
|
||||
continue;
|
||||
|
||||
spin_lock_irq(&fa->fa_lock);
|
||||
fa->fa_file = NULL;
|
||||
spin_unlock_irq(&fa->fa_lock);
|
||||
|
||||
*fp = fa->fa_next;
|
||||
call_rcu(&fa->fa_rcu, fasync_free_rcu);
|
||||
filp->f_flags &= ~FASYNC;
|
||||
result = 1;
|
||||
break;
|
||||
}
|
||||
spin_unlock(&fasync_lock);
|
||||
spin_unlock(&filp->f_lock);
|
||||
return result;
|
||||
}
|
||||
|
||||
struct fasync_struct *fasync_alloc(void)
|
||||
{
|
||||
return kmem_cache_alloc(fasync_cache, GFP_KERNEL);
|
||||
}
|
||||
|
||||
/*
|
||||
* NOTE! This can be used only for unused fasync entries:
|
||||
* entries that actually got inserted on the fasync list
|
||||
* need to be released by rcu - see fasync_remove_entry.
|
||||
*/
|
||||
void fasync_free(struct fasync_struct *new)
|
||||
{
|
||||
kmem_cache_free(fasync_cache, new);
|
||||
}
|
||||
|
||||
/*
|
||||
* Insert a new entry into the fasync list. Return the pointer to the
|
||||
* old one if we didn't use the new one.
|
||||
*
|
||||
* NOTE! It is very important that the FASYNC flag always
|
||||
* match the state "is the filp on a fasync list".
|
||||
*/
|
||||
struct fasync_struct *fasync_insert_entry(int fd, struct file *filp, struct fasync_struct **fapp, struct fasync_struct *new)
|
||||
{
|
||||
struct fasync_struct *fa, **fp;
|
||||
|
||||
spin_lock(&filp->f_lock);
|
||||
spin_lock(&fasync_lock);
|
||||
for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
|
||||
if (fa->fa_file != filp)
|
||||
continue;
|
||||
|
||||
spin_lock_irq(&fa->fa_lock);
|
||||
fa->fa_fd = fd;
|
||||
spin_unlock_irq(&fa->fa_lock);
|
||||
goto out;
|
||||
}
|
||||
|
||||
spin_lock_init(&new->fa_lock);
|
||||
new->magic = FASYNC_MAGIC;
|
||||
new->fa_file = filp;
|
||||
new->fa_fd = fd;
|
||||
new->fa_next = *fapp;
|
||||
rcu_assign_pointer(*fapp, new);
|
||||
filp->f_flags |= FASYNC;
|
||||
|
||||
out:
|
||||
spin_unlock(&fasync_lock);
|
||||
spin_unlock(&filp->f_lock);
|
||||
return fa;
|
||||
}
|
||||
|
||||
/*
|
||||
* Add a fasync entry. Return negative on error, positive if
|
||||
* added, and zero if did nothing but change an existing one.
|
||||
*/
|
||||
static int fasync_add_entry(int fd, struct file *filp, struct fasync_struct **fapp)
|
||||
{
|
||||
struct fasync_struct *new;
|
||||
|
||||
new = fasync_alloc();
|
||||
if (!new)
|
||||
return -ENOMEM;
|
||||
|
||||
/*
|
||||
* fasync_insert_entry() returns the old (update) entry if
|
||||
* it existed.
|
||||
*
|
||||
* So free the (unused) new entry and return 0 to let the
|
||||
* caller know that we didn't add any new fasync entries.
|
||||
*/
|
||||
if (fasync_insert_entry(fd, filp, fapp, new)) {
|
||||
fasync_free(new);
|
||||
return 0;
|
||||
}
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
/*
|
||||
* fasync_helper() is used by almost all character device drivers
|
||||
* to set up the fasync queue, and for regular files by the file
|
||||
* lease code. It returns negative on error, 0 if it did no changes
|
||||
* and positive if it added/deleted the entry.
|
||||
*/
|
||||
int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fapp)
|
||||
{
|
||||
if (!on)
|
||||
return fasync_remove_entry(filp, fapp);
|
||||
return fasync_add_entry(fd, filp, fapp);
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(fasync_helper);
|
||||
|
||||
/*
|
||||
* rcu_read_lock() is held
|
||||
*/
|
||||
static void kill_fasync_rcu(struct fasync_struct *fa, int sig, int band)
|
||||
{
|
||||
while (fa) {
|
||||
struct fown_struct *fown;
|
||||
unsigned long flags;
|
||||
|
||||
if (fa->magic != FASYNC_MAGIC) {
|
||||
printk(KERN_ERR "kill_fasync: bad magic number in "
|
||||
"fasync_struct!\n");
|
||||
return;
|
||||
}
|
||||
spin_lock_irqsave(&fa->fa_lock, flags);
|
||||
if (fa->fa_file) {
|
||||
fown = &fa->fa_file->f_owner;
|
||||
/* Don't send SIGURG to processes which have not set a
|
||||
queued signum: SIGURG has its own default signalling
|
||||
mechanism. */
|
||||
if (!(sig == SIGURG && fown->signum == 0))
|
||||
send_sigio(fown, fa->fa_fd, band);
|
||||
}
|
||||
spin_unlock_irqrestore(&fa->fa_lock, flags);
|
||||
fa = rcu_dereference(fa->fa_next);
|
||||
}
|
||||
}
|
||||
|
||||
void kill_fasync(struct fasync_struct **fp, int sig, int band)
|
||||
{
|
||||
/* First a quick test without locking: usually
|
||||
* the list is empty.
|
||||
*/
|
||||
if (*fp) {
|
||||
rcu_read_lock();
|
||||
kill_fasync_rcu(rcu_dereference(*fp), sig, band);
|
||||
rcu_read_unlock();
|
||||
}
|
||||
}
|
||||
EXPORT_SYMBOL(kill_fasync);
|
||||
|
||||
static int __init fcntl_init(void)
|
||||
{
|
||||
/*
|
||||
* Please add new bits here to ensure allocation uniqueness.
|
||||
* Exceptions: O_NONBLOCK is a two bit define on parisc; O_NDELAY
|
||||
* is defined as O_NONBLOCK on some platforms and not on others.
|
||||
*/
|
||||
BUILD_BUG_ON(20 - 1 /* for O_RDONLY being 0 */ != HWEIGHT32(
|
||||
O_RDONLY | O_WRONLY | O_RDWR |
|
||||
O_CREAT | O_EXCL | O_NOCTTY |
|
||||
O_TRUNC | O_APPEND | /* O_NONBLOCK | */
|
||||
__O_SYNC | O_DSYNC | FASYNC |
|
||||
O_DIRECT | O_LARGEFILE | O_DIRECTORY |
|
||||
O_NOFOLLOW | O_NOATIME | O_CLOEXEC |
|
||||
__FMODE_EXEC | O_PATH | __O_TMPFILE
|
||||
));
|
||||
|
||||
fasync_cache = kmem_cache_create("fasync_cache",
|
||||
sizeof(struct fasync_struct), 0, SLAB_PANIC, NULL);
|
||||
return 0;
|
||||
}
|
||||
|
||||
module_init(fcntl_init)
|
||||
Loading…
Add table
Add a link
Reference in a new issue