drivers/hv/hv_common.c

1 // SPDX-License-Identifier: GPL-2.0
5  * Hyper-V. This file is specifically for code that must be
6  * built-in to the kernel image when CONFIG_HYPERV is set
26 #include <linux/dma-map-ops.h>
28 #include <asm/hyperv-tlfs.h>
33  * Hyper-V specific globals so they are shared across all architectures and are
66  * Hyper-V specific initialization and shutdown code that is
92  * the guest page size may not be the same as the Hyper-V page
93  * size. We depend upon kmalloc() aligning power-of-two size
95  * allocated memory appears to Hyper-V as a page of the size
131  * Boolean to control whether to report panic messages over Hyper-V.
139  * reported to Hyper-V on panic.
179 	/* Don't notify Hyper-V unless we have a die oops event or panic. */  in hv_die_panic_notify_crash()
188 		regs = ((struct die_args *)args)->regs;  in hv_die_panic_notify_crash()
192 	 * Hyper-V should be notified only once about a panic/die. If we will  in hv_die_panic_notify_crash()
204  * buffer and call into Hyper-V to transfer the data.
217 	 * Write dump contents to the page. No need to synchronize; panic should  in hv_kmsg_dump()
218 	 * be single-threaded.  in hv_kmsg_dump()
228 	 * registers are no-op when the NOTIFY_MSG flag is set.  in hv_kmsg_dump()
237 	 * Let Hyper-V know there is crash data available along with  in hv_kmsg_dump()
246 	.dump = hv_kmsg_dump,
266 		pr_err("Hyper-V: panic message page memory allocation failed\n");  in hv_kmsg_dump_register()
272 		pr_err("Hyper-V: kmsg dump register error 0x%x\n", ret);  in hv_kmsg_dump_register()
286 	 * Hyper-V expects to get crash register data or kmsg when  in hv_common_init()
296 		pr_info("Hyper-V: enabling crash_kexec_post_notifiers\n");  in hv_common_init()
300 		 * is enabled by default in non-isolated guests and  in hv_common_init()
307 			pr_err("Hyper-V: sysctl table register error");  in hv_common_init()
323 	 * Allocate the per-CPU state for the hypercall input arg.  in hv_common_init()
325 	 * (per-CPU) hypercall input page and thus this failure is  in hv_common_init()
326 	 * fatal on Hyper-V.  in hv_common_init()
331 	/* Allocate the per-CPU state for output arg for root */  in hv_common_init()
341 		return -ENOMEM;  in hv_common_init()
351  * Hyper-V specific initialization and die code for
377 			return -ENOMEM;  in hv_common_cpu_init()
397 		 * hyperv_pcpu_input_arg is not NULL, set_memory_decrypted() ->  in hv_common_cpu_init()
398 		 * ... -> cpa_flush()-> ... -> __send_ipi_mask_ex() tries to  in hv_common_cpu_init()
427 	 * may be used by the Hyper-V vPCI driver in reassigning interrupts  in hv_common_cpu_die()
449 	 * Hypercall input/output addresses should also be 8-byte aligned.  in hv_query_ext_cap()
476 		pr_err("Hyper-V: Extended query capabilities hypercall failed 0x%llx\n",  in hv_query_ext_cap()
488 	 * Hyper-V does not offer a vIOMMU in the guest  in hv_setup_dma_ops()
502  * Default function to read the Hyper-V reference counter, independent
503  * of whether Hyper-V enlightened clocks/timers are being used. But on
504  * architectures where it is used, Hyper-V enlightenment code in
515 /* These __weak functions provide default "no-op" behavior and
517  * for which the default "no-op" behavior is sufficient can leave
519  * functions in arch-specific code.