ipc: merge ipc_rcu and kern_ipc_perm (dba4cdd3) · Commits · e / devices / android_kernel_fairphone_FP4

include/linux/ipc.h

+3 −0

Original line number	Original line	Diff line number	Diff line
	@@ -20,6 +20,9 @@ struct kern_ipc_perm {
	umode_t mode;		umode_t mode;
	unsigned long seq;		unsigned long seq;
	void *security;		void *security;

			struct rcu_head rcu;
			atomic_t refcount;
	} ____cacheline_aligned_in_smp;		} ____cacheline_aligned_in_smp;

	#endif /* _LINUX_IPC_H */		#endif /* _LINUX_IPC_H */

ipc/msg.c

+11 −8

Original line number	Original line	Diff line number	Diff line
	@@ -97,8 +97,8 @@ static inline void msg_rmid(struct ipc_namespace ns, struct msg_queue s)

	static void msg_rcu_free(struct rcu_head *head)		static void msg_rcu_free(struct rcu_head *head)
	{		{
	struct ipc_rcu *p = container_of(head, struct ipc_rcu, rcu);		struct kern_ipc_perm *p = container_of(head, struct kern_ipc_perm, rcu);
	struct msg_queue *msq = ipc_rcu_to_struct(p);		struct msg_queue *msq = container_of(p, struct msg_queue, q_perm);

	security_msg_queue_free(msq);		security_msg_queue_free(msq);
	ipc_rcu_free(head);		ipc_rcu_free(head);
	@@ -118,7 +118,10 @@ static int newque(struct ipc_namespace ns, struct ipc_params params)
	key_t key = params->key;		key_t key = params->key;
	int msgflg = params->flg;		int msgflg = params->flg;

	msq = ipc_rcu_alloc(sizeof(*msq));		BUILD_BUG_ON(offsetof(struct msg_queue, q_perm) != 0);

			msq = container_of(ipc_rcu_alloc(sizeof(*msq)), struct msg_queue,
			q_perm);
	if (!msq)		if (!msq)
	return -ENOMEM;		return -ENOMEM;

	@@ -128,7 +131,7 @@ static int newque(struct ipc_namespace ns, struct ipc_params params)
	msq->q_perm.security = NULL;		msq->q_perm.security = NULL;
	retval = security_msg_queue_alloc(msq);		retval = security_msg_queue_alloc(msq);
	if (retval) {		if (retval) {
	ipc_rcu_putref(msq, ipc_rcu_free);		ipc_rcu_putref(&msq->q_perm, ipc_rcu_free);
	return retval;		return retval;
	}		}

	@@ -144,7 +147,7 @@ static int newque(struct ipc_namespace ns, struct ipc_params params)
	/* ipc_addid() locks msq upon success. */		/* ipc_addid() locks msq upon success. */
	id = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni);		id = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni);
	if (id < 0) {		if (id < 0) {
	ipc_rcu_putref(msq, msg_rcu_free);		ipc_rcu_putref(&msq->q_perm, msg_rcu_free);
	return id;		return id;
	}		}

	@@ -249,7 +252,7 @@ static void freeque(struct ipc_namespace ns, struct kern_ipc_perm ipcp)
	free_msg(msg);		free_msg(msg);
	}		}
	atomic_sub(msq->q_cbytes, &ns->msg_bytes);		atomic_sub(msq->q_cbytes, &ns->msg_bytes);
	ipc_rcu_putref(msq, msg_rcu_free);		ipc_rcu_putref(&msq->q_perm, msg_rcu_free);
	}		}

	/*		/*
	@@ -688,7 +691,7 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext,
	/* enqueue the sender and prepare to block */		/* enqueue the sender and prepare to block */
	ss_add(msq, &s, msgsz);		ss_add(msq, &s, msgsz);

	if (!ipc_rcu_getref(msq)) {		if (!ipc_rcu_getref(&msq->q_perm)) {
	err = -EIDRM;		err = -EIDRM;
	goto out_unlock0;		goto out_unlock0;
	}		}
	@@ -700,7 +703,7 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext,
	rcu_read_lock();		rcu_read_lock();
	ipc_lock_object(&msq->q_perm);		ipc_lock_object(&msq->q_perm);

	ipc_rcu_putref(msq, msg_rcu_free);		ipc_rcu_putref(&msq->q_perm, msg_rcu_free);
	/* raced with RMID? */		/* raced with RMID? */
	if (!ipc_valid_object(&msq->q_perm)) {		if (!ipc_valid_object(&msq->q_perm)) {
	err = -EIDRM;		err = -EIDRM;

ipc/sem.c

+17 −17

Original line number	Original line	Diff line number	Diff line
	@@ -260,8 +260,8 @@ static void merge_queues(struct sem_array *sma)

	static void sem_rcu_free(struct rcu_head *head)		static void sem_rcu_free(struct rcu_head *head)
	{		{
	struct ipc_rcu *p = container_of(head, struct ipc_rcu, rcu);		struct kern_ipc_perm *p = container_of(head, struct kern_ipc_perm, rcu);
	struct sem_array *sma = ipc_rcu_to_struct(p);		struct sem_array *sma = container_of(p, struct sem_array, sem_perm);

	security_sem_free(sma);		security_sem_free(sma);
	ipc_rcu_free(head);		ipc_rcu_free(head);
	@@ -438,7 +438,7 @@ static inline struct sem_array sem_obtain_object_check(struct ipc_namespace ns
	static inline void sem_lock_and_putref(struct sem_array *sma)		static inline void sem_lock_and_putref(struct sem_array *sma)
	{		{
	sem_lock(sma, NULL, -1);		sem_lock(sma, NULL, -1);
	ipc_rcu_putref(sma, sem_rcu_free);		ipc_rcu_putref(&sma->sem_perm, sem_rcu_free);
	}		}

	static inline void sem_rmid(struct ipc_namespace ns, struct sem_array s)		static inline void sem_rmid(struct ipc_namespace ns, struct sem_array s)
	@@ -469,20 +469,20 @@ static int newary(struct ipc_namespace ns, struct ipc_params params)
	if (ns->used_sems + nsems > ns->sc_semmns)		if (ns->used_sems + nsems > ns->sc_semmns)
	return -ENOSPC;		return -ENOSPC;

			BUILD_BUG_ON(offsetof(struct sem_array, sem_perm) != 0);

	size = sizeof(sma) + nsems sizeof(sma->sems[0]);		size = sizeof(sma) + nsems sizeof(sma->sems[0]);
	sma = ipc_rcu_alloc(size);		sma = container_of(ipc_rcu_alloc(size), struct sem_array, sem_perm);
	if (!sma)		if (!sma)
	return -ENOMEM;		return -ENOMEM;

	memset(sma, 0, size);

	sma->sem_perm.mode = (semflg & S_IRWXUGO);		sma->sem_perm.mode = (semflg & S_IRWXUGO);
	sma->sem_perm.key = key;		sma->sem_perm.key = key;

	sma->sem_perm.security = NULL;		sma->sem_perm.security = NULL;
	retval = security_sem_alloc(sma);		retval = security_sem_alloc(sma);
	if (retval) {		if (retval) {
	ipc_rcu_putref(sma, ipc_rcu_free);		ipc_rcu_putref(&sma->sem_perm, ipc_rcu_free);
	return retval;		return retval;
	}		}

	@@ -502,7 +502,7 @@ static int newary(struct ipc_namespace ns, struct ipc_params params)

	id = ipc_addid(&sem_ids(ns), &sma->sem_perm, ns->sc_semmni);		id = ipc_addid(&sem_ids(ns), &sma->sem_perm, ns->sc_semmni);
	if (id < 0) {		if (id < 0) {
	ipc_rcu_putref(sma, sem_rcu_free);		ipc_rcu_putref(&sma->sem_perm, sem_rcu_free);
	return id;		return id;
	}		}
	ns->used_sems += nsems;		ns->used_sems += nsems;
	@@ -1122,7 +1122,7 @@ static void freeary(struct ipc_namespace ns, struct kern_ipc_perm ipcp)

	wake_up_q(&wake_q);		wake_up_q(&wake_q);
	ns->used_sems -= sma->sem_nsems;		ns->used_sems -= sma->sem_nsems;
	ipc_rcu_putref(sma, sem_rcu_free);		ipc_rcu_putref(&sma->sem_perm, sem_rcu_free);
	}		}

	static unsigned long copy_semid_to_user(void __user buf, struct semid64_ds in, int version)		static unsigned long copy_semid_to_user(void __user buf, struct semid64_ds in, int version)
	@@ -1362,7 +1362,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum,
	goto out_unlock;		goto out_unlock;
	}		}
	if (nsems > SEMMSL_FAST) {		if (nsems > SEMMSL_FAST) {
	if (!ipc_rcu_getref(sma)) {		if (!ipc_rcu_getref(&sma->sem_perm)) {
	err = -EIDRM;		err = -EIDRM;
	goto out_unlock;		goto out_unlock;
	}		}
	@@ -1370,7 +1370,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum,
	rcu_read_unlock();		rcu_read_unlock();
	sem_io = ipc_alloc(sizeof(ushort)*nsems);		sem_io = ipc_alloc(sizeof(ushort)*nsems);
	if (sem_io == NULL) {		if (sem_io == NULL) {
	ipc_rcu_putref(sma, sem_rcu_free);		ipc_rcu_putref(&sma->sem_perm, sem_rcu_free);
	return -ENOMEM;		return -ENOMEM;
	}		}

	@@ -1395,7 +1395,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum,
	int i;		int i;
	struct sem_undo *un;		struct sem_undo *un;

	if (!ipc_rcu_getref(sma)) {		if (!ipc_rcu_getref(&sma->sem_perm)) {
	err = -EIDRM;		err = -EIDRM;
	goto out_rcu_wakeup;		goto out_rcu_wakeup;
	}		}
	@@ -1404,20 +1404,20 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum,
	if (nsems > SEMMSL_FAST) {		if (nsems > SEMMSL_FAST) {
	sem_io = ipc_alloc(sizeof(ushort)*nsems);		sem_io = ipc_alloc(sizeof(ushort)*nsems);
	if (sem_io == NULL) {		if (sem_io == NULL) {
	ipc_rcu_putref(sma, sem_rcu_free);		ipc_rcu_putref(&sma->sem_perm, sem_rcu_free);
	return -ENOMEM;		return -ENOMEM;
	}		}
	}		}

	if (copy_from_user(sem_io, p, nsems*sizeof(ushort))) {		if (copy_from_user(sem_io, p, nsems*sizeof(ushort))) {
	ipc_rcu_putref(sma, sem_rcu_free);		ipc_rcu_putref(&sma->sem_perm, sem_rcu_free);
	err = -EFAULT;		err = -EFAULT;
	goto out_free;		goto out_free;
	}		}

	for (i = 0; i < nsems; i++) {		for (i = 0; i < nsems; i++) {
	if (sem_io[i] > SEMVMX) {		if (sem_io[i] > SEMVMX) {
	ipc_rcu_putref(sma, sem_rcu_free);		ipc_rcu_putref(&sma->sem_perm, sem_rcu_free);
	err = -ERANGE;		err = -ERANGE;
	goto out_free;		goto out_free;
	}		}
	@@ -1699,7 +1699,7 @@ static struct sem_undo find_alloc_undo(struct ipc_namespace ns, int semid)
	}		}

	nsems = sma->sem_nsems;		nsems = sma->sem_nsems;
	if (!ipc_rcu_getref(sma)) {		if (!ipc_rcu_getref(&sma->sem_perm)) {
	rcu_read_unlock();		rcu_read_unlock();
	un = ERR_PTR(-EIDRM);		un = ERR_PTR(-EIDRM);
	goto out;		goto out;
	@@ -1709,7 +1709,7 @@ static struct sem_undo find_alloc_undo(struct ipc_namespace ns, int semid)
	/* step 2: allocate new undo structure */		/* step 2: allocate new undo structure */
	new = kzalloc(sizeof(struct sem_undo) + sizeof(short)*nsems, GFP_KERNEL);		new = kzalloc(sizeof(struct sem_undo) + sizeof(short)*nsems, GFP_KERNEL);
	if (!new) {		if (!new) {
	ipc_rcu_putref(sma, sem_rcu_free);		ipc_rcu_putref(&sma->sem_perm, sem_rcu_free);
	return ERR_PTR(-ENOMEM);		return ERR_PTR(-ENOMEM);
	}		}

ipc/shm.c

+11 −7

Original line number	Original line	Diff line number	Diff line
	@@ -174,9 +174,10 @@ static inline void shm_lock_by_ptr(struct shmid_kernel *ipcp)

	static void shm_rcu_free(struct rcu_head *head)		static void shm_rcu_free(struct rcu_head *head)
	{		{
	struct ipc_rcu *p = container_of(head, struct ipc_rcu, rcu);		struct kern_ipc_perm *ptr = container_of(head, struct kern_ipc_perm,
	struct shmid_kernel *shp = ipc_rcu_to_struct(p);		rcu);
			struct shmid_kernel *shp = container_of(ptr, struct shmid_kernel,
			shm_perm);
	security_shm_free(shp);		security_shm_free(shp);
	ipc_rcu_free(head);		ipc_rcu_free(head);
	}		}
	@@ -241,7 +242,7 @@ static void shm_destroy(struct ipc_namespace ns, struct shmid_kernel shp)
	user_shm_unlock(i_size_read(file_inode(shm_file)),		user_shm_unlock(i_size_read(file_inode(shm_file)),
	shp->mlock_user);		shp->mlock_user);
	fput(shm_file);		fput(shm_file);
	ipc_rcu_putref(shp, shm_rcu_free);		ipc_rcu_putref(&shp->shm_perm, shm_rcu_free);
	}		}

	/*		/*
	@@ -542,7 +543,10 @@ static int newseg(struct ipc_namespace ns, struct ipc_params params)
	ns->shm_tot + numpages > ns->shm_ctlall)		ns->shm_tot + numpages > ns->shm_ctlall)
	return -ENOSPC;		return -ENOSPC;

	shp = ipc_rcu_alloc(sizeof(*shp));		BUILD_BUG_ON(offsetof(struct shmid_kernel, shm_perm) != 0);

			shp = container_of(ipc_rcu_alloc(sizeof(*shp)), struct shmid_kernel,
			shm_perm);
	if (!shp)		if (!shp)
	return -ENOMEM;		return -ENOMEM;

	@@ -553,7 +557,7 @@ static int newseg(struct ipc_namespace ns, struct ipc_params params)
	shp->shm_perm.security = NULL;		shp->shm_perm.security = NULL;
	error = security_shm_alloc(shp);		error = security_shm_alloc(shp);
	if (error) {		if (error) {
	ipc_rcu_putref(shp, ipc_rcu_free);		ipc_rcu_putref(&shp->shm_perm, ipc_rcu_free);
	return error;		return error;
	}		}

	@@ -624,7 +628,7 @@ static int newseg(struct ipc_namespace ns, struct ipc_params params)
	user_shm_unlock(size, shp->mlock_user);		user_shm_unlock(size, shp->mlock_user);
	fput(file);		fput(file);
	no_file:		no_file:
	ipc_rcu_putref(shp, shm_rcu_free);		ipc_rcu_putref(&shp->shm_perm, shm_rcu_free);
	return error;		return error;
	}		}

ipc/util.c

+17 −18

Original line number	Original line	Diff line number	Diff line
	@@ -418,46 +418,45 @@ void ipc_free(void *ptr)
	}		}

	/**		/**
	* ipc_rcu_alloc - allocate ipc and rcu space		* ipc_rcu_alloc - allocate ipc space
	* @size: size desired		* @size: size desired
	*		*
	* Allocate memory for the rcu header structure + the object.		* Allocate memory for an ipc object.
	* Returns the pointer to the object or NULL upon failure.		* The first member must be struct kern_ipc_perm.
	*/		*/
	void *ipc_rcu_alloc(int size)		struct kern_ipc_perm *ipc_rcu_alloc(int size)
	{		{
	/*		/*
	* We prepend the allocation with the rcu struct		* We prepend the allocation with the rcu struct
	*/		*/
	struct ipc_rcu *out = ipc_alloc(sizeof(struct ipc_rcu) + size);		struct kern_ipc_perm *out = ipc_alloc(size);
	if (unlikely(!out))		if (unlikely(!out))
	return NULL;		return NULL;

			memset(out, 0, size);
	atomic_set(&out->refcount, 1);		atomic_set(&out->refcount, 1);
	return out + 1;		return out;
	}		}

	int ipc_rcu_getref(void *ptr)		int ipc_rcu_getref(struct kern_ipc_perm *ptr)
	{		{
	struct ipc_rcu p = ((struct ipc_rcu )ptr) - 1;		return atomic_inc_not_zero(&ptr->refcount);

	return atomic_inc_not_zero(&p->refcount);
	}		}

	void ipc_rcu_putref(void ptr, void (func)(struct rcu_head *head))		void ipc_rcu_putref(struct kern_ipc_perm *ptr,
			void (func)(struct rcu_head head))
	{		{
	struct ipc_rcu p = ((struct ipc_rcu )ptr) - 1;		if (!atomic_dec_and_test(&ptr->refcount))

	if (!atomic_dec_and_test(&p->refcount))
	return;		return;

	call_rcu(&p->rcu, func);		call_rcu(&ptr->rcu, func);
	}		}

	void ipc_rcu_free(struct rcu_head *head)		void ipc_rcu_free(struct rcu_head *h)
	{		{
	struct ipc_rcu *p = container_of(head, struct ipc_rcu, rcu);		struct kern_ipc_perm *ptr = container_of(h, struct kern_ipc_perm, rcu);

	kvfree(p);		kvfree(ptr);
	}		}

	/**		/**