[PATCH] powerpc: special-case ibm,suspend-me RTAS call (91dc182c) · Commits · 戴 / test

arch/powerpc/kernel/rtas.c

+95 −1

Original line number	Diff line number	Diff line
		@@ -36,6 +36,11 @@ struct rtas_t rtas = {
		.lock = SPIN_LOCK_UNLOCKED
		};

		struct rtas_suspend_me_data {
		long waiting;
		struct rtas_args *args;
		};

		EXPORT_SYMBOL(rtas);

		DEFINE_SPINLOCK(rtas_data_buf_lock);
		@@ -556,6 +561,80 @@ void rtas_os_term(char *str)
		} while (status == RTAS_BUSY);
		}

		static int ibm_suspend_me_token = RTAS_UNKNOWN_SERVICE;
		#ifdef CONFIG_PPC_PSERIES
		static void rtas_percpu_suspend_me(void *info)
		{
		long rc;
		long flags;
		struct rtas_suspend_me_data *data =
		(struct rtas_suspend_me_data *)info;

		/*
		* We use "waiting" to indicate our state. As long
		* as it is >0, we are still trying to all join up.
		* If it goes to 0, we have successfully joined up and
		* one thread got H_Continue. If any error happens,
		* we set it to <0.
		*/
		local_irq_save(flags);
		do {
		rc = plpar_hcall_norets(H_JOIN);
		smp_rmb();
		} while (rc == H_Success && data->waiting > 0);
		if (rc == H_Success)
		goto out;

		if (rc == H_Continue) {
		data->waiting = 0;
		rtas_call(ibm_suspend_me_token, 0, 1,
		data->args->args);
		} else {
		data->waiting = -EBUSY;
		printk(KERN_ERR "Error on H_Join hypervisor call\n");
		}

		out:
		/* before we restore interrupts, make sure we don't
		* generate a spurious soft lockup errors
		*/
		touch_softlockup_watchdog();
		local_irq_restore(flags);
		return;
		}

		static int rtas_ibm_suspend_me(struct rtas_args *args)
		{
		int i;

		struct rtas_suspend_me_data data;

		data.waiting = 1;
		data.args = args;

		/* Call function on all CPUs. One of us will make the
		* rtas call
		*/
		if (on_each_cpu(rtas_percpu_suspend_me, &data, 1, 0))
		data.waiting = -EINVAL;

		if (data.waiting != 0)
		printk(KERN_ERR "Error doing global join\n");

		/* Prod each CPU. This won't hurt, and will wake
		* anyone we successfully put to sleep with H_Join
		*/
		for_each_cpu(i)
		plpar_hcall_norets(H_PROD, i);

		return data.waiting;
		}
		#else /* CONFIG_PPC_PSERIES */
		static int rtas_ibm_suspend_me(struct rtas_args *args)
		{
		return -ENOSYS;
		}
		#endif

		asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
		{
		@@ -563,6 +642,7 @@ asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
		unsigned long flags;
		char buff_copy, errbuf = NULL;
		int nargs;
		int rc;

		if (!capable(CAP_SYS_ADMIN))
		return -EPERM;
		@@ -581,6 +661,17 @@ asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
		nargs * sizeof(rtas_arg_t)) != 0)
		return -EFAULT;

		if (args.token == RTAS_UNKNOWN_SERVICE)
		return -EINVAL;

		/* Need to handle ibm,suspend_me call specially */
		if (args.token == ibm_suspend_me_token) {
		rc = rtas_ibm_suspend_me(&args);
		if (rc)
		return rc;
		goto copy_return;
		}

		buff_copy = get_errorlog_buffer();

		spin_lock_irqsave(&rtas.lock, flags);
		@@ -604,6 +695,7 @@ asmlinkage int ppc_rtas(struct rtas_args __user *uargs)
		kfree(buff_copy);
		}

		copy_return:
		/* Copy out args. */
		if (copy_to_user(uargs->args + nargs,
		args.args + nargs,
		@@ -675,8 +767,10 @@ void __init rtas_initialize(void)
		* the stop-self token if any
		*/
		#ifdef CONFIG_PPC64
		if (_machine == PLATFORM_PSERIES_LPAR)
		if (_machine == PLATFORM_PSERIES_LPAR) {
		rtas_region = min(lmb.rmo_size, RTAS_INSTANTIATE_MAX);
		ibm_suspend_me_token = rtas_token("ibm,suspend-me");
		}
		#endif
		rtas_rmo_buf = lmb_alloc_base(RTAS_RMOBUF_MAX, PAGE_SIZE, rtas_region);

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