Hi Alexander,
Today's linux-next merge of the kvm-ppc tree got a conflict in
arch/powerpc/include/asm/kvm_para.h between commit c3617f72036c ("UAPI:
(Scripted) Disintegrate arch/powerpc/include/asm") from the powerpc-merge
tree and commit 549d62d889b4 ("KVM: PPC: use definitions in epapr header
for hcalls") from the kvm-ppc tree.
I fixed it up (see at the end) and can carry the fix as necessary (no action
is required, though you need to remember to tell Linus about this).
I also added this merge fix patch:
From 61d39136e4228e62e27c11ac8d27cd6664b39639 Mon Sep 17 00:00:00 2001
From: Stephen Rothwell <[email protected]>
Date: Thu, 11 Oct 2012 12:13:51 +1100
Subject: [PATCH] KVM: PPC: fix fallout from UAPI changes
Signed-off-by: Stephen Rothwell <[email protected]>
---
arch/powerpc/include/asm/epapr_hcalls.h | 511 --------------------------
arch/powerpc/include/uapi/asm/Kbuild | 1 +
arch/powerpc/include/uapi/asm/epapr_hcalls.h | 511 ++++++++++++++++++++++++++
arch/powerpc/include/uapi/asm/kvm_para.h | 7 +-
4 files changed, 516 insertions(+), 514 deletions(-)
delete mode 100644 arch/powerpc/include/asm/epapr_hcalls.h
create mode 100644 arch/powerpc/include/uapi/asm/epapr_hcalls.h
diff --git a/arch/powerpc/include/asm/epapr_hcalls.h b/arch/powerpc/include/asm/epapr_hcalls.h
deleted file mode 100644
index b8d9445..0000000
--- a/arch/powerpc/include/asm/epapr_hcalls.h
+++ /dev/null
@@ -1,511 +0,0 @@
-/*
- * ePAPR hcall interface
- *
- * Copyright 2008-2011 Freescale Semiconductor, Inc.
- *
- * Author: Timur Tabi <[email protected]>
- *
- * This file is provided under a dual BSD/GPL license. When using or
- * redistributing this file, you may do so under either license.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- * * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * * Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * * Neither the name of Freescale Semiconductor nor the
- * names of its contributors may be used to endorse or promote products
- * derived from this software without specific prior written permission.
- *
- *
- * ALTERNATIVELY, this software may be distributed under the terms of the
- * GNU General Public License ("GPL") as published by the Free Software
- * Foundation, either version 2 of that License or (at your option) any
- * later version.
- *
- * THIS SOFTWARE IS PROVIDED BY Freescale Semiconductor ``AS IS'' AND ANY
- * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL Freescale Semiconductor BE LIABLE FOR ANY
- * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-/* A "hypercall" is an "sc 1" instruction. This header file file provides C
- * wrapper functions for the ePAPR hypervisor interface. It is inteded
- * for use by Linux device drivers and other operating systems.
- *
- * The hypercalls are implemented as inline assembly, rather than assembly
- * language functions in a .S file, for optimization. It allows
- * the caller to issue the hypercall instruction directly, improving both
- * performance and memory footprint.
- */
-
-#ifndef _EPAPR_HCALLS_H
-#define _EPAPR_HCALLS_H
-
-#define EV_BYTE_CHANNEL_SEND 1
-#define EV_BYTE_CHANNEL_RECEIVE 2
-#define EV_BYTE_CHANNEL_POLL 3
-#define EV_INT_SET_CONFIG 4
-#define EV_INT_GET_CONFIG 5
-#define EV_INT_SET_MASK 6
-#define EV_INT_GET_MASK 7
-#define EV_INT_IACK 9
-#define EV_INT_EOI 10
-#define EV_INT_SEND_IPI 11
-#define EV_INT_SET_TASK_PRIORITY 12
-#define EV_INT_GET_TASK_PRIORITY 13
-#define EV_DOORBELL_SEND 14
-#define EV_MSGSND 15
-#define EV_IDLE 16
-
-/* vendor ID: epapr */
-#define EV_LOCAL_VENDOR_ID 0 /* for private use */
-#define EV_EPAPR_VENDOR_ID 1
-#define EV_FSL_VENDOR_ID 2 /* Freescale Semiconductor */
-#define EV_IBM_VENDOR_ID 3 /* IBM */
-#define EV_GHS_VENDOR_ID 4 /* Green Hills Software */
-#define EV_ENEA_VENDOR_ID 5 /* Enea */
-#define EV_WR_VENDOR_ID 6 /* Wind River Systems */
-#define EV_AMCC_VENDOR_ID 7 /* Applied Micro Circuits */
-#define EV_KVM_VENDOR_ID 42 /* KVM */
-
-/* The max number of bytes that a byte channel can send or receive per call */
-#define EV_BYTE_CHANNEL_MAX_BYTES 16
-
-
-#define _EV_HCALL_TOKEN(id, num) (((id) << 16) | (num))
-#define EV_HCALL_TOKEN(hcall_num) _EV_HCALL_TOKEN(EV_EPAPR_VENDOR_ID, hcall_num)
-
-/* epapr return codes */
-#define EV_SUCCESS 0
-#define EV_EPERM 1 /* Operation not permitted */
-#define EV_ENOENT 2 /* Entry Not Found */
-#define EV_EIO 3 /* I/O error occured */
-#define EV_EAGAIN 4 /* The operation had insufficient
- * resources to complete and should be
- * retried
- */
-#define EV_ENOMEM 5 /* There was insufficient memory to
- * complete the operation */
-#define EV_EFAULT 6 /* Bad guest address */
-#define EV_ENODEV 7 /* No such device */
-#define EV_EINVAL 8 /* An argument supplied to the hcall
- was out of range or invalid */
-#define EV_INTERNAL 9 /* An internal error occured */
-#define EV_CONFIG 10 /* A configuration error was detected */
-#define EV_INVALID_STATE 11 /* The object is in an invalid state */
-#define EV_UNIMPLEMENTED 12 /* Unimplemented hypercall */
-#define EV_BUFFER_OVERFLOW 13 /* Caller-supplied buffer too small */
-
-#ifndef __ASSEMBLY__
-#include <linux/types.h>
-#include <linux/errno.h>
-#include <asm/byteorder.h>
-
-/*
- * Hypercall register clobber list
- *
- * These macros are used to define the list of clobbered registers during a
- * hypercall. Technically, registers r0 and r3-r12 are always clobbered,
- * but the gcc inline assembly syntax does not allow us to specify registers
- * on the clobber list that are also on the input/output list. Therefore,
- * the lists of clobbered registers depends on the number of register
- * parmeters ("+r" and "=r") passed to the hypercall.
- *
- * Each assembly block should use one of the HCALL_CLOBBERSx macros. As a
- * general rule, 'x' is the number of parameters passed to the assembly
- * block *except* for r11.
- *
- * If you're not sure, just use the smallest value of 'x' that does not
- * generate a compilation error. Because these are static inline functions,
- * the compiler will only check the clobber list for a function if you
- * compile code that calls that function.
- *
- * r3 and r11 are not included in any clobbers list because they are always
- * listed as output registers.
- *
- * XER, CTR, and LR are currently listed as clobbers because it's uncertain
- * whether they will be clobbered.
- *
- * Note that r11 can be used as an output parameter.
- *
- * The "memory" clobber is only necessary for hcalls where the Hypervisor
- * will read or write guest memory. However, we add it to all hcalls because
- * the impact is minimal, and we want to ensure that it's present for the
- * hcalls that need it.
-*/
-
-/* List of common clobbered registers. Do not use this macro. */
-#define EV_HCALL_CLOBBERS "r0", "r12", "xer", "ctr", "lr", "cc", "memory"
-
-#define EV_HCALL_CLOBBERS8 EV_HCALL_CLOBBERS
-#define EV_HCALL_CLOBBERS7 EV_HCALL_CLOBBERS8, "r10"
-#define EV_HCALL_CLOBBERS6 EV_HCALL_CLOBBERS7, "r9"
-#define EV_HCALL_CLOBBERS5 EV_HCALL_CLOBBERS6, "r8"
-#define EV_HCALL_CLOBBERS4 EV_HCALL_CLOBBERS5, "r7"
-#define EV_HCALL_CLOBBERS3 EV_HCALL_CLOBBERS4, "r6"
-#define EV_HCALL_CLOBBERS2 EV_HCALL_CLOBBERS3, "r5"
-#define EV_HCALL_CLOBBERS1 EV_HCALL_CLOBBERS2, "r4"
-
-extern bool epapr_paravirt_enabled;
-extern u32 epapr_hypercall_start[];
-
-/*
- * We use "uintptr_t" to define a register because it's guaranteed to be a
- * 32-bit integer on a 32-bit platform, and a 64-bit integer on a 64-bit
- * platform.
- *
- * All registers are either input/output or output only. Registers that are
- * initialized before making the hypercall are input/output. All
- * input/output registers are represented with "+r". Output-only registers
- * are represented with "=r". Do not specify any unused registers. The
- * clobber list will tell the compiler that the hypercall modifies those
- * registers, which is good enough.
- */
-
-/**
- * ev_int_set_config - configure the specified interrupt
- * @interrupt: the interrupt number
- * @config: configuration for this interrupt
- * @priority: interrupt priority
- * @destination: destination CPU number
- *
- * Returns 0 for success, or an error code.
- */
-static inline unsigned int ev_int_set_config(unsigned int interrupt,
- uint32_t config, unsigned int priority, uint32_t destination)
-{
- register uintptr_t r11 __asm__("r11");
- register uintptr_t r3 __asm__("r3");
- register uintptr_t r4 __asm__("r4");
- register uintptr_t r5 __asm__("r5");
- register uintptr_t r6 __asm__("r6");
-
- r11 = EV_HCALL_TOKEN(EV_INT_SET_CONFIG);
- r3 = interrupt;
- r4 = config;
- r5 = priority;
- r6 = destination;
-
- asm volatile("bl epapr_hypercall_start"
- : "+r" (r11), "+r" (r3), "+r" (r4), "+r" (r5), "+r" (r6)
- : : EV_HCALL_CLOBBERS4
- );
-
- return r3;
-}
-
-/**
- * ev_int_get_config - return the config of the specified interrupt
- * @interrupt: the interrupt number
- * @config: returned configuration for this interrupt
- * @priority: returned interrupt priority
- * @destination: returned destination CPU number
- *
- * Returns 0 for success, or an error code.
- */
-static inline unsigned int ev_int_get_config(unsigned int interrupt,
- uint32_t *config, unsigned int *priority, uint32_t *destination)
-{
- register uintptr_t r11 __asm__("r11");
- register uintptr_t r3 __asm__("r3");
- register uintptr_t r4 __asm__("r4");
- register uintptr_t r5 __asm__("r5");
- register uintptr_t r6 __asm__("r6");
-
- r11 = EV_HCALL_TOKEN(EV_INT_GET_CONFIG);
- r3 = interrupt;
-
- asm volatile("bl epapr_hypercall_start"
- : "+r" (r11), "+r" (r3), "=r" (r4), "=r" (r5), "=r" (r6)
- : : EV_HCALL_CLOBBERS4
- );
-
- *config = r4;
- *priority = r5;
- *destination = r6;
-
- return r3;
-}
-
-/**
- * ev_int_set_mask - sets the mask for the specified interrupt source
- * @interrupt: the interrupt number
- * @mask: 0=enable interrupts, 1=disable interrupts
- *
- * Returns 0 for success, or an error code.
- */
-static inline unsigned int ev_int_set_mask(unsigned int interrupt,
- unsigned int mask)
-{
- register uintptr_t r11 __asm__("r11");
- register uintptr_t r3 __asm__("r3");
- register uintptr_t r4 __asm__("r4");
-
- r11 = EV_HCALL_TOKEN(EV_INT_SET_MASK);
- r3 = interrupt;
- r4 = mask;
-
- asm volatile("bl epapr_hypercall_start"
- : "+r" (r11), "+r" (r3), "+r" (r4)
- : : EV_HCALL_CLOBBERS2
- );
-
- return r3;
-}
-
-/**
- * ev_int_get_mask - returns the mask for the specified interrupt source
- * @interrupt: the interrupt number
- * @mask: returned mask for this interrupt (0=enabled, 1=disabled)
- *
- * Returns 0 for success, or an error code.
- */
-static inline unsigned int ev_int_get_mask(unsigned int interrupt,
- unsigned int *mask)
-{
- register uintptr_t r11 __asm__("r11");
- register uintptr_t r3 __asm__("r3");
- register uintptr_t r4 __asm__("r4");
-
- r11 = EV_HCALL_TOKEN(EV_INT_GET_MASK);
- r3 = interrupt;
-
- asm volatile("bl epapr_hypercall_start"
- : "+r" (r11), "+r" (r3), "=r" (r4)
- : : EV_HCALL_CLOBBERS2
- );
-
- *mask = r4;
-
- return r3;
-}
-
-/**
- * ev_int_eoi - signal the end of interrupt processing
- * @interrupt: the interrupt number
- *
- * This function signals the end of processing for the the specified
- * interrupt, which must be the interrupt currently in service. By
- * definition, this is also the highest-priority interrupt.
- *
- * Returns 0 for success, or an error code.
- */
-static inline unsigned int ev_int_eoi(unsigned int interrupt)
-{
- register uintptr_t r11 __asm__("r11");
- register uintptr_t r3 __asm__("r3");
-
- r11 = EV_HCALL_TOKEN(EV_INT_EOI);
- r3 = interrupt;
-
- asm volatile("bl epapr_hypercall_start"
- : "+r" (r11), "+r" (r3)
- : : EV_HCALL_CLOBBERS1
- );
-
- return r3;
-}
-
-/**
- * ev_byte_channel_send - send characters to a byte stream
- * @handle: byte stream handle
- * @count: (input) num of chars to send, (output) num chars sent
- * @buffer: pointer to a 16-byte buffer
- *
- * @buffer must be at least 16 bytes long, because all 16 bytes will be
- * read from memory into registers, even if count < 16.
- *
- * Returns 0 for success, or an error code.
- */
-static inline unsigned int ev_byte_channel_send(unsigned int handle,
- unsigned int *count, const char buffer[EV_BYTE_CHANNEL_MAX_BYTES])
-{
- register uintptr_t r11 __asm__("r11");
- register uintptr_t r3 __asm__("r3");
- register uintptr_t r4 __asm__("r4");
- register uintptr_t r5 __asm__("r5");
- register uintptr_t r6 __asm__("r6");
- register uintptr_t r7 __asm__("r7");
- register uintptr_t r8 __asm__("r8");
- const uint32_t *p = (const uint32_t *) buffer;
-
- r11 = EV_HCALL_TOKEN(EV_BYTE_CHANNEL_SEND);
- r3 = handle;
- r4 = *count;
- r5 = be32_to_cpu(p[0]);
- r6 = be32_to_cpu(p[1]);
- r7 = be32_to_cpu(p[2]);
- r8 = be32_to_cpu(p[3]);
-
- asm volatile("bl epapr_hypercall_start"
- : "+r" (r11), "+r" (r3),
- "+r" (r4), "+r" (r5), "+r" (r6), "+r" (r7), "+r" (r8)
- : : EV_HCALL_CLOBBERS6
- );
-
- *count = r4;
-
- return r3;
-}
-
-/**
- * ev_byte_channel_receive - fetch characters from a byte channel
- * @handle: byte channel handle
- * @count: (input) max num of chars to receive, (output) num chars received
- * @buffer: pointer to a 16-byte buffer
- *
- * The size of @buffer must be at least 16 bytes, even if you request fewer
- * than 16 characters, because we always write 16 bytes to @buffer. This is
- * for performance reasons.
- *
- * Returns 0 for success, or an error code.
- */
-static inline unsigned int ev_byte_channel_receive(unsigned int handle,
- unsigned int *count, char buffer[EV_BYTE_CHANNEL_MAX_BYTES])
-{
- register uintptr_t r11 __asm__("r11");
- register uintptr_t r3 __asm__("r3");
- register uintptr_t r4 __asm__("r4");
- register uintptr_t r5 __asm__("r5");
- register uintptr_t r6 __asm__("r6");
- register uintptr_t r7 __asm__("r7");
- register uintptr_t r8 __asm__("r8");
- uint32_t *p = (uint32_t *) buffer;
-
- r11 = EV_HCALL_TOKEN(EV_BYTE_CHANNEL_RECEIVE);
- r3 = handle;
- r4 = *count;
-
- asm volatile("bl epapr_hypercall_start"
- : "+r" (r11), "+r" (r3), "+r" (r4),
- "=r" (r5), "=r" (r6), "=r" (r7), "=r" (r8)
- : : EV_HCALL_CLOBBERS6
- );
-
- *count = r4;
- p[0] = cpu_to_be32(r5);
- p[1] = cpu_to_be32(r6);
- p[2] = cpu_to_be32(r7);
- p[3] = cpu_to_be32(r8);
-
- return r3;
-}
-
-/**
- * ev_byte_channel_poll - returns the status of the byte channel buffers
- * @handle: byte channel handle
- * @rx_count: returned count of bytes in receive queue
- * @tx_count: returned count of free space in transmit queue
- *
- * This function reports the amount of data in the receive queue (i.e. the
- * number of bytes you can read), and the amount of free space in the transmit
- * queue (i.e. the number of bytes you can write).
- *
- * Returns 0 for success, or an error code.
- */
-static inline unsigned int ev_byte_channel_poll(unsigned int handle,
- unsigned int *rx_count, unsigned int *tx_count)
-{
- register uintptr_t r11 __asm__("r11");
- register uintptr_t r3 __asm__("r3");
- register uintptr_t r4 __asm__("r4");
- register uintptr_t r5 __asm__("r5");
-
- r11 = EV_HCALL_TOKEN(EV_BYTE_CHANNEL_POLL);
- r3 = handle;
-
- asm volatile("bl epapr_hypercall_start"
- : "+r" (r11), "+r" (r3), "=r" (r4), "=r" (r5)
- : : EV_HCALL_CLOBBERS3
- );
-
- *rx_count = r4;
- *tx_count = r5;
-
- return r3;
-}
-
-/**
- * ev_int_iack - acknowledge an interrupt
- * @handle: handle to the target interrupt controller
- * @vector: returned interrupt vector
- *
- * If handle is zero, the function returns the next interrupt source
- * number to be handled irrespective of the hierarchy or cascading
- * of interrupt controllers. If non-zero, specifies a handle to the
- * interrupt controller that is the target of the acknowledge.
- *
- * Returns 0 for success, or an error code.
- */
-static inline unsigned int ev_int_iack(unsigned int handle,
- unsigned int *vector)
-{
- register uintptr_t r11 __asm__("r11");
- register uintptr_t r3 __asm__("r3");
- register uintptr_t r4 __asm__("r4");
-
- r11 = EV_HCALL_TOKEN(EV_INT_IACK);
- r3 = handle;
-
- asm volatile("bl epapr_hypercall_start"
- : "+r" (r11), "+r" (r3), "=r" (r4)
- : : EV_HCALL_CLOBBERS2
- );
-
- *vector = r4;
-
- return r3;
-}
-
-/**
- * ev_doorbell_send - send a doorbell to another partition
- * @handle: doorbell send handle
- *
- * Returns 0 for success, or an error code.
- */
-static inline unsigned int ev_doorbell_send(unsigned int handle)
-{
- register uintptr_t r11 __asm__("r11");
- register uintptr_t r3 __asm__("r3");
-
- r11 = EV_HCALL_TOKEN(EV_DOORBELL_SEND);
- r3 = handle;
-
- asm volatile("bl epapr_hypercall_start"
- : "+r" (r11), "+r" (r3)
- : : EV_HCALL_CLOBBERS1
- );
-
- return r3;
-}
-
-/**
- * ev_idle -- wait for next interrupt on this core
- *
- * Returns 0 for success, or an error code.
- */
-static inline unsigned int ev_idle(void)
-{
- register uintptr_t r11 __asm__("r11");
- register uintptr_t r3 __asm__("r3");
-
- r11 = EV_HCALL_TOKEN(EV_IDLE);
-
- asm volatile("bl epapr_hypercall_start"
- : "+r" (r11), "=r" (r3)
- : : EV_HCALL_CLOBBERS1
- );
-
- return r3;
-}
-#endif /* !__ASSEMBLY__ */
-#endif
diff --git a/arch/powerpc/include/uapi/asm/Kbuild b/arch/powerpc/include/uapi/asm/Kbuild
index a33c3c0..c62a732 100644
--- a/arch/powerpc/include/uapi/asm/Kbuild
+++ b/arch/powerpc/include/uapi/asm/Kbuild
@@ -8,6 +8,7 @@ header-y += byteorder.h
header-y += cputable.h
header-y += elf.h
header-y += errno.h
+header-y += epapr_hcalls.h
header-y += fcntl.h
header-y += ioctl.h
header-y += ioctls.h
diff --git a/arch/powerpc/include/uapi/asm/epapr_hcalls.h b/arch/powerpc/include/uapi/asm/epapr_hcalls.h
new file mode 100644
index 0000000..b8d9445
--- /dev/null
+++ b/arch/powerpc/include/uapi/asm/epapr_hcalls.h
@@ -0,0 +1,511 @@
+/*
+ * ePAPR hcall interface
+ *
+ * Copyright 2008-2011 Freescale Semiconductor, Inc.
+ *
+ * Author: Timur Tabi <[email protected]>
+ *
+ * This file is provided under a dual BSD/GPL license. When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * * Neither the name of Freescale Semiconductor nor the
+ * names of its contributors may be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ *
+ * ALTERNATIVELY, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") as published by the Free Software
+ * Foundation, either version 2 of that License or (at your option) any
+ * later version.
+ *
+ * THIS SOFTWARE IS PROVIDED BY Freescale Semiconductor ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL Freescale Semiconductor BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/* A "hypercall" is an "sc 1" instruction. This header file file provides C
+ * wrapper functions for the ePAPR hypervisor interface. It is inteded
+ * for use by Linux device drivers and other operating systems.
+ *
+ * The hypercalls are implemented as inline assembly, rather than assembly
+ * language functions in a .S file, for optimization. It allows
+ * the caller to issue the hypercall instruction directly, improving both
+ * performance and memory footprint.
+ */
+
+#ifndef _EPAPR_HCALLS_H
+#define _EPAPR_HCALLS_H
+
+#define EV_BYTE_CHANNEL_SEND 1
+#define EV_BYTE_CHANNEL_RECEIVE 2
+#define EV_BYTE_CHANNEL_POLL 3
+#define EV_INT_SET_CONFIG 4
+#define EV_INT_GET_CONFIG 5
+#define EV_INT_SET_MASK 6
+#define EV_INT_GET_MASK 7
+#define EV_INT_IACK 9
+#define EV_INT_EOI 10
+#define EV_INT_SEND_IPI 11
+#define EV_INT_SET_TASK_PRIORITY 12
+#define EV_INT_GET_TASK_PRIORITY 13
+#define EV_DOORBELL_SEND 14
+#define EV_MSGSND 15
+#define EV_IDLE 16
+
+/* vendor ID: epapr */
+#define EV_LOCAL_VENDOR_ID 0 /* for private use */
+#define EV_EPAPR_VENDOR_ID 1
+#define EV_FSL_VENDOR_ID 2 /* Freescale Semiconductor */
+#define EV_IBM_VENDOR_ID 3 /* IBM */
+#define EV_GHS_VENDOR_ID 4 /* Green Hills Software */
+#define EV_ENEA_VENDOR_ID 5 /* Enea */
+#define EV_WR_VENDOR_ID 6 /* Wind River Systems */
+#define EV_AMCC_VENDOR_ID 7 /* Applied Micro Circuits */
+#define EV_KVM_VENDOR_ID 42 /* KVM */
+
+/* The max number of bytes that a byte channel can send or receive per call */
+#define EV_BYTE_CHANNEL_MAX_BYTES 16
+
+
+#define _EV_HCALL_TOKEN(id, num) (((id) << 16) | (num))
+#define EV_HCALL_TOKEN(hcall_num) _EV_HCALL_TOKEN(EV_EPAPR_VENDOR_ID, hcall_num)
+
+/* epapr return codes */
+#define EV_SUCCESS 0
+#define EV_EPERM 1 /* Operation not permitted */
+#define EV_ENOENT 2 /* Entry Not Found */
+#define EV_EIO 3 /* I/O error occured */
+#define EV_EAGAIN 4 /* The operation had insufficient
+ * resources to complete and should be
+ * retried
+ */
+#define EV_ENOMEM 5 /* There was insufficient memory to
+ * complete the operation */
+#define EV_EFAULT 6 /* Bad guest address */
+#define EV_ENODEV 7 /* No such device */
+#define EV_EINVAL 8 /* An argument supplied to the hcall
+ was out of range or invalid */
+#define EV_INTERNAL 9 /* An internal error occured */
+#define EV_CONFIG 10 /* A configuration error was detected */
+#define EV_INVALID_STATE 11 /* The object is in an invalid state */
+#define EV_UNIMPLEMENTED 12 /* Unimplemented hypercall */
+#define EV_BUFFER_OVERFLOW 13 /* Caller-supplied buffer too small */
+
+#ifndef __ASSEMBLY__
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <asm/byteorder.h>
+
+/*
+ * Hypercall register clobber list
+ *
+ * These macros are used to define the list of clobbered registers during a
+ * hypercall. Technically, registers r0 and r3-r12 are always clobbered,
+ * but the gcc inline assembly syntax does not allow us to specify registers
+ * on the clobber list that are also on the input/output list. Therefore,
+ * the lists of clobbered registers depends on the number of register
+ * parmeters ("+r" and "=r") passed to the hypercall.
+ *
+ * Each assembly block should use one of the HCALL_CLOBBERSx macros. As a
+ * general rule, 'x' is the number of parameters passed to the assembly
+ * block *except* for r11.
+ *
+ * If you're not sure, just use the smallest value of 'x' that does not
+ * generate a compilation error. Because these are static inline functions,
+ * the compiler will only check the clobber list for a function if you
+ * compile code that calls that function.
+ *
+ * r3 and r11 are not included in any clobbers list because they are always
+ * listed as output registers.
+ *
+ * XER, CTR, and LR are currently listed as clobbers because it's uncertain
+ * whether they will be clobbered.
+ *
+ * Note that r11 can be used as an output parameter.
+ *
+ * The "memory" clobber is only necessary for hcalls where the Hypervisor
+ * will read or write guest memory. However, we add it to all hcalls because
+ * the impact is minimal, and we want to ensure that it's present for the
+ * hcalls that need it.
+*/
+
+/* List of common clobbered registers. Do not use this macro. */
+#define EV_HCALL_CLOBBERS "r0", "r12", "xer", "ctr", "lr", "cc", "memory"
+
+#define EV_HCALL_CLOBBERS8 EV_HCALL_CLOBBERS
+#define EV_HCALL_CLOBBERS7 EV_HCALL_CLOBBERS8, "r10"
+#define EV_HCALL_CLOBBERS6 EV_HCALL_CLOBBERS7, "r9"
+#define EV_HCALL_CLOBBERS5 EV_HCALL_CLOBBERS6, "r8"
+#define EV_HCALL_CLOBBERS4 EV_HCALL_CLOBBERS5, "r7"
+#define EV_HCALL_CLOBBERS3 EV_HCALL_CLOBBERS4, "r6"
+#define EV_HCALL_CLOBBERS2 EV_HCALL_CLOBBERS3, "r5"
+#define EV_HCALL_CLOBBERS1 EV_HCALL_CLOBBERS2, "r4"
+
+extern bool epapr_paravirt_enabled;
+extern u32 epapr_hypercall_start[];
+
+/*
+ * We use "uintptr_t" to define a register because it's guaranteed to be a
+ * 32-bit integer on a 32-bit platform, and a 64-bit integer on a 64-bit
+ * platform.
+ *
+ * All registers are either input/output or output only. Registers that are
+ * initialized before making the hypercall are input/output. All
+ * input/output registers are represented with "+r". Output-only registers
+ * are represented with "=r". Do not specify any unused registers. The
+ * clobber list will tell the compiler that the hypercall modifies those
+ * registers, which is good enough.
+ */
+
+/**
+ * ev_int_set_config - configure the specified interrupt
+ * @interrupt: the interrupt number
+ * @config: configuration for this interrupt
+ * @priority: interrupt priority
+ * @destination: destination CPU number
+ *
+ * Returns 0 for success, or an error code.
+ */
+static inline unsigned int ev_int_set_config(unsigned int interrupt,
+ uint32_t config, unsigned int priority, uint32_t destination)
+{
+ register uintptr_t r11 __asm__("r11");
+ register uintptr_t r3 __asm__("r3");
+ register uintptr_t r4 __asm__("r4");
+ register uintptr_t r5 __asm__("r5");
+ register uintptr_t r6 __asm__("r6");
+
+ r11 = EV_HCALL_TOKEN(EV_INT_SET_CONFIG);
+ r3 = interrupt;
+ r4 = config;
+ r5 = priority;
+ r6 = destination;
+
+ asm volatile("bl epapr_hypercall_start"
+ : "+r" (r11), "+r" (r3), "+r" (r4), "+r" (r5), "+r" (r6)
+ : : EV_HCALL_CLOBBERS4
+ );
+
+ return r3;
+}
+
+/**
+ * ev_int_get_config - return the config of the specified interrupt
+ * @interrupt: the interrupt number
+ * @config: returned configuration for this interrupt
+ * @priority: returned interrupt priority
+ * @destination: returned destination CPU number
+ *
+ * Returns 0 for success, or an error code.
+ */
+static inline unsigned int ev_int_get_config(unsigned int interrupt,
+ uint32_t *config, unsigned int *priority, uint32_t *destination)
+{
+ register uintptr_t r11 __asm__("r11");
+ register uintptr_t r3 __asm__("r3");
+ register uintptr_t r4 __asm__("r4");
+ register uintptr_t r5 __asm__("r5");
+ register uintptr_t r6 __asm__("r6");
+
+ r11 = EV_HCALL_TOKEN(EV_INT_GET_CONFIG);
+ r3 = interrupt;
+
+ asm volatile("bl epapr_hypercall_start"
+ : "+r" (r11), "+r" (r3), "=r" (r4), "=r" (r5), "=r" (r6)
+ : : EV_HCALL_CLOBBERS4
+ );
+
+ *config = r4;
+ *priority = r5;
+ *destination = r6;
+
+ return r3;
+}
+
+/**
+ * ev_int_set_mask - sets the mask for the specified interrupt source
+ * @interrupt: the interrupt number
+ * @mask: 0=enable interrupts, 1=disable interrupts
+ *
+ * Returns 0 for success, or an error code.
+ */
+static inline unsigned int ev_int_set_mask(unsigned int interrupt,
+ unsigned int mask)
+{
+ register uintptr_t r11 __asm__("r11");
+ register uintptr_t r3 __asm__("r3");
+ register uintptr_t r4 __asm__("r4");
+
+ r11 = EV_HCALL_TOKEN(EV_INT_SET_MASK);
+ r3 = interrupt;
+ r4 = mask;
+
+ asm volatile("bl epapr_hypercall_start"
+ : "+r" (r11), "+r" (r3), "+r" (r4)
+ : : EV_HCALL_CLOBBERS2
+ );
+
+ return r3;
+}
+
+/**
+ * ev_int_get_mask - returns the mask for the specified interrupt source
+ * @interrupt: the interrupt number
+ * @mask: returned mask for this interrupt (0=enabled, 1=disabled)
+ *
+ * Returns 0 for success, or an error code.
+ */
+static inline unsigned int ev_int_get_mask(unsigned int interrupt,
+ unsigned int *mask)
+{
+ register uintptr_t r11 __asm__("r11");
+ register uintptr_t r3 __asm__("r3");
+ register uintptr_t r4 __asm__("r4");
+
+ r11 = EV_HCALL_TOKEN(EV_INT_GET_MASK);
+ r3 = interrupt;
+
+ asm volatile("bl epapr_hypercall_start"
+ : "+r" (r11), "+r" (r3), "=r" (r4)
+ : : EV_HCALL_CLOBBERS2
+ );
+
+ *mask = r4;
+
+ return r3;
+}
+
+/**
+ * ev_int_eoi - signal the end of interrupt processing
+ * @interrupt: the interrupt number
+ *
+ * This function signals the end of processing for the the specified
+ * interrupt, which must be the interrupt currently in service. By
+ * definition, this is also the highest-priority interrupt.
+ *
+ * Returns 0 for success, or an error code.
+ */
+static inline unsigned int ev_int_eoi(unsigned int interrupt)
+{
+ register uintptr_t r11 __asm__("r11");
+ register uintptr_t r3 __asm__("r3");
+
+ r11 = EV_HCALL_TOKEN(EV_INT_EOI);
+ r3 = interrupt;
+
+ asm volatile("bl epapr_hypercall_start"
+ : "+r" (r11), "+r" (r3)
+ : : EV_HCALL_CLOBBERS1
+ );
+
+ return r3;
+}
+
+/**
+ * ev_byte_channel_send - send characters to a byte stream
+ * @handle: byte stream handle
+ * @count: (input) num of chars to send, (output) num chars sent
+ * @buffer: pointer to a 16-byte buffer
+ *
+ * @buffer must be at least 16 bytes long, because all 16 bytes will be
+ * read from memory into registers, even if count < 16.
+ *
+ * Returns 0 for success, or an error code.
+ */
+static inline unsigned int ev_byte_channel_send(unsigned int handle,
+ unsigned int *count, const char buffer[EV_BYTE_CHANNEL_MAX_BYTES])
+{
+ register uintptr_t r11 __asm__("r11");
+ register uintptr_t r3 __asm__("r3");
+ register uintptr_t r4 __asm__("r4");
+ register uintptr_t r5 __asm__("r5");
+ register uintptr_t r6 __asm__("r6");
+ register uintptr_t r7 __asm__("r7");
+ register uintptr_t r8 __asm__("r8");
+ const uint32_t *p = (const uint32_t *) buffer;
+
+ r11 = EV_HCALL_TOKEN(EV_BYTE_CHANNEL_SEND);
+ r3 = handle;
+ r4 = *count;
+ r5 = be32_to_cpu(p[0]);
+ r6 = be32_to_cpu(p[1]);
+ r7 = be32_to_cpu(p[2]);
+ r8 = be32_to_cpu(p[3]);
+
+ asm volatile("bl epapr_hypercall_start"
+ : "+r" (r11), "+r" (r3),
+ "+r" (r4), "+r" (r5), "+r" (r6), "+r" (r7), "+r" (r8)
+ : : EV_HCALL_CLOBBERS6
+ );
+
+ *count = r4;
+
+ return r3;
+}
+
+/**
+ * ev_byte_channel_receive - fetch characters from a byte channel
+ * @handle: byte channel handle
+ * @count: (input) max num of chars to receive, (output) num chars received
+ * @buffer: pointer to a 16-byte buffer
+ *
+ * The size of @buffer must be at least 16 bytes, even if you request fewer
+ * than 16 characters, because we always write 16 bytes to @buffer. This is
+ * for performance reasons.
+ *
+ * Returns 0 for success, or an error code.
+ */
+static inline unsigned int ev_byte_channel_receive(unsigned int handle,
+ unsigned int *count, char buffer[EV_BYTE_CHANNEL_MAX_BYTES])
+{
+ register uintptr_t r11 __asm__("r11");
+ register uintptr_t r3 __asm__("r3");
+ register uintptr_t r4 __asm__("r4");
+ register uintptr_t r5 __asm__("r5");
+ register uintptr_t r6 __asm__("r6");
+ register uintptr_t r7 __asm__("r7");
+ register uintptr_t r8 __asm__("r8");
+ uint32_t *p = (uint32_t *) buffer;
+
+ r11 = EV_HCALL_TOKEN(EV_BYTE_CHANNEL_RECEIVE);
+ r3 = handle;
+ r4 = *count;
+
+ asm volatile("bl epapr_hypercall_start"
+ : "+r" (r11), "+r" (r3), "+r" (r4),
+ "=r" (r5), "=r" (r6), "=r" (r7), "=r" (r8)
+ : : EV_HCALL_CLOBBERS6
+ );
+
+ *count = r4;
+ p[0] = cpu_to_be32(r5);
+ p[1] = cpu_to_be32(r6);
+ p[2] = cpu_to_be32(r7);
+ p[3] = cpu_to_be32(r8);
+
+ return r3;
+}
+
+/**
+ * ev_byte_channel_poll - returns the status of the byte channel buffers
+ * @handle: byte channel handle
+ * @rx_count: returned count of bytes in receive queue
+ * @tx_count: returned count of free space in transmit queue
+ *
+ * This function reports the amount of data in the receive queue (i.e. the
+ * number of bytes you can read), and the amount of free space in the transmit
+ * queue (i.e. the number of bytes you can write).
+ *
+ * Returns 0 for success, or an error code.
+ */
+static inline unsigned int ev_byte_channel_poll(unsigned int handle,
+ unsigned int *rx_count, unsigned int *tx_count)
+{
+ register uintptr_t r11 __asm__("r11");
+ register uintptr_t r3 __asm__("r3");
+ register uintptr_t r4 __asm__("r4");
+ register uintptr_t r5 __asm__("r5");
+
+ r11 = EV_HCALL_TOKEN(EV_BYTE_CHANNEL_POLL);
+ r3 = handle;
+
+ asm volatile("bl epapr_hypercall_start"
+ : "+r" (r11), "+r" (r3), "=r" (r4), "=r" (r5)
+ : : EV_HCALL_CLOBBERS3
+ );
+
+ *rx_count = r4;
+ *tx_count = r5;
+
+ return r3;
+}
+
+/**
+ * ev_int_iack - acknowledge an interrupt
+ * @handle: handle to the target interrupt controller
+ * @vector: returned interrupt vector
+ *
+ * If handle is zero, the function returns the next interrupt source
+ * number to be handled irrespective of the hierarchy or cascading
+ * of interrupt controllers. If non-zero, specifies a handle to the
+ * interrupt controller that is the target of the acknowledge.
+ *
+ * Returns 0 for success, or an error code.
+ */
+static inline unsigned int ev_int_iack(unsigned int handle,
+ unsigned int *vector)
+{
+ register uintptr_t r11 __asm__("r11");
+ register uintptr_t r3 __asm__("r3");
+ register uintptr_t r4 __asm__("r4");
+
+ r11 = EV_HCALL_TOKEN(EV_INT_IACK);
+ r3 = handle;
+
+ asm volatile("bl epapr_hypercall_start"
+ : "+r" (r11), "+r" (r3), "=r" (r4)
+ : : EV_HCALL_CLOBBERS2
+ );
+
+ *vector = r4;
+
+ return r3;
+}
+
+/**
+ * ev_doorbell_send - send a doorbell to another partition
+ * @handle: doorbell send handle
+ *
+ * Returns 0 for success, or an error code.
+ */
+static inline unsigned int ev_doorbell_send(unsigned int handle)
+{
+ register uintptr_t r11 __asm__("r11");
+ register uintptr_t r3 __asm__("r3");
+
+ r11 = EV_HCALL_TOKEN(EV_DOORBELL_SEND);
+ r3 = handle;
+
+ asm volatile("bl epapr_hypercall_start"
+ : "+r" (r11), "+r" (r3)
+ : : EV_HCALL_CLOBBERS1
+ );
+
+ return r3;
+}
+
+/**
+ * ev_idle -- wait for next interrupt on this core
+ *
+ * Returns 0 for success, or an error code.
+ */
+static inline unsigned int ev_idle(void)
+{
+ register uintptr_t r11 __asm__("r11");
+ register uintptr_t r3 __asm__("r3");
+
+ r11 = EV_HCALL_TOKEN(EV_IDLE);
+
+ asm volatile("bl epapr_hypercall_start"
+ : "+r" (r11), "=r" (r3)
+ : : EV_HCALL_CLOBBERS1
+ );
+
+ return r3;
+}
+#endif /* !__ASSEMBLY__ */
+#endif
diff --git a/arch/powerpc/include/uapi/asm/kvm_para.h b/arch/powerpc/include/uapi/asm/kvm_para.h
index 5e04383..34d8b1c 100644
--- a/arch/powerpc/include/uapi/asm/kvm_para.h
+++ b/arch/powerpc/include/uapi/asm/kvm_para.h
@@ -75,9 +75,10 @@ struct kvm_vcpu_arch_shared {
};
#define KVM_SC_MAGIC_R0 0x4b564d21 /* "KVM!" */
-#define HC_VENDOR_KVM (42 << 16)
-#define HC_EV_SUCCESS 0
-#define HC_EV_UNIMPLEMENTED 12
+
+#define KVM_HCALL_TOKEN(num) _EV_HCALL_TOKEN(EV_KVM_VENDOR_ID, num)
+
+#include <asm/epapr_hcalls.h>
#define KVM_FEATURE_MAGIC_PAGE 1
--
1.7.10.280.gaa39
--
Cheers,
Stephen Rothwell [email protected]
diff --cc arch/powerpc/include/asm/kvm_para.h
index 9365860,a168ce3..0000000
--- a/arch/powerpc/include/asm/kvm_para.h
+++ b/arch/powerpc/include/asm/kvm_para.h
@@@ -19,9 -19,76 +19,8 @@@
#ifndef __POWERPC_KVM_PARA_H__
#define __POWERPC_KVM_PARA_H__
-#include <linux/types.h>
-
-/*
- * Additions to this struct must only occur at the end, and should be
- * accompanied by a KVM_MAGIC_FEAT flag to advertise that they are present
- * (albeit not necessarily relevant to the current target hardware platform).
- *
- * Struct fields are always 32 or 64 bit aligned, depending on them being 32
- * or 64 bit wide respectively.
- *
- * See Documentation/virtual/kvm/ppc-pv.txt
- */
-struct kvm_vcpu_arch_shared {
- __u64 scratch1;
- __u64 scratch2;
- __u64 scratch3;
- __u64 critical; /* Guest may not get interrupts if == r1 */
- __u64 sprg0;
- __u64 sprg1;
- __u64 sprg2;
- __u64 sprg3;
- __u64 srr0;
- __u64 srr1;
- __u64 dar; /* dear on BookE */
- __u64 msr;
- __u32 dsisr;
- __u32 int_pending; /* Tells the guest if we have an interrupt */
- __u32 sr[16];
- __u32 mas0;
- __u32 mas1;
- __u64 mas7_3;
- __u64 mas2;
- __u32 mas4;
- __u32 mas6;
- __u32 esr;
- __u32 pir;
-
- /*
- * SPRG4-7 are user-readable, so we can only keep these consistent
- * between the shared area and the real registers when there's an
- * intervening exit to KVM. This also applies to SPRG3 on some
- * chips.
- *
- * This suffices for access by guest userspace, since in PR-mode
- * KVM, an exit must occur when changing the guest's MSR[PR].
- * If the guest kernel writes to SPRG3-7 via the shared area, it
- * must also use the shared area for reading while in kernel space.
- */
- __u64 sprg4;
- __u64 sprg5;
- __u64 sprg6;
- __u64 sprg7;
-};
-
-#define KVM_SC_MAGIC_R0 0x4b564d21 /* "KVM!" */
-
-#define KVM_HCALL_TOKEN(num) _EV_HCALL_TOKEN(EV_KVM_VENDOR_ID, num)
-
-#include <asm/epapr_hcalls.h>
-
-#define KVM_FEATURE_MAGIC_PAGE 1
-
-#define KVM_MAGIC_FEAT_SR (1 << 0)
-
-/* MASn, ESR, PIR, and high SPRGs */
-#define KVM_MAGIC_FEAT_MAS0_TO_SPRG7 (1 << 1)
-
-#ifdef __KERNEL__
+#include <uapi/asm/kvm_para.h>
-
#ifdef CONFIG_KVM_GUEST
#include <linux/of.h>
On Wed, Oct 10, 2012 at 8:18 PM, Stephen Rothwell <[email protected]> wrote:
> arch/powerpc/include/asm/epapr_hcalls.h | 511 --------------------------
> arch/powerpc/include/uapi/asm/Kbuild | 1 +
> arch/powerpc/include/uapi/asm/epapr_hcalls.h | 511 ++++++++++++++++++++++++++
What is include/uapi? epapr_hcalls.h is not a user-space header file.
I don't remember seeing the original patch which moved it, so I don't
know where this comes from.
--
Timur Tabi
Linux kernel developer at Freescale
On Thu, 11 Oct 2012 01:47:13 +0000 Tabi Timur-B04825 <[email protected]> wrote:
>
> On Wed, Oct 10, 2012 at 8:18 PM, Stephen Rothwell <[email protected]> wrote:
>
> > arch/powerpc/include/asm/epapr_hcalls.h | 511 --------------------------
> > arch/powerpc/include/uapi/asm/Kbuild | 1 +
> > arch/powerpc/include/uapi/asm/epapr_hcalls.h | 511 ++++++++++++++++++++++++++
>
> What is include/uapi? epapr_hcalls.h is not a user-space header file.
> I don't remember seeing the original patch which moved it, so I don't
> know where this comes from.
Commit 549d62d889b4 ("KVM: PPC: use definitions in epapr header
for hcalls") from the kvm-ppc tree added an include of asm/epapr_hcall.h
to the user visible part of asm/kvm_para.h so asm/epapr_hcall.h became a
user visible header file.
The UAPI changes are moving the user visible parts of export header files
into a separate include directory called uapi.
--
Cheers,
Stephen Rothwell [email protected]
http://www.canb.auug.org.au/~sfr/
On Wed, Oct 10, 2012 at 9:47 PM, Stephen Rothwell <[email protected]> wrote:
> Commit 549d62d889b4 ("KVM: PPC: use definitions in epapr header
> for hcalls") from the kvm-ppc tree added an include of asm/epapr_hcall.h
> to the user visible part of asm/kvm_para.h so asm/epapr_hcall.h became a
> user visible header file.
Any real user-space code that tries to call any of the functions in
epapr_hcall.h will cause an exception.
Claiming that kernel header files that KVM needs are suddenly
user-space header files doesn't make much sense to me, but I guess
it's not my decision.
--
Timur Tabi
Linux kernel developer at Freescale
Tabi Timur-B04825 <[email protected]> wrote:
> What is include/uapi?
Take a look at http://lwn.net/Articles/507794/
David
On 11.10.2012, at 05:32, Tabi Timur-B04825 wrote:
> On Wed, Oct 10, 2012 at 9:47 PM, Stephen Rothwell <[email protected]> wrote:
>
>> Commit 549d62d889b4 ("KVM: PPC: use definitions in epapr header
>> for hcalls") from the kvm-ppc tree added an include of asm/epapr_hcall.h
>> to the user visible part of asm/kvm_para.h so asm/epapr_hcall.h became a
>> user visible header file.
>
> Any real user-space code that tries to call any of the functions in
> epapr_hcall.h will cause an exception.
>
> Claiming that kernel header files that KVM needs are suddenly
> user-space header files doesn't make much sense to me, but I guess
> it's not my decision.
This is about kvm_host.h, which is the part that is exported to user space. It usually contains constants and structs that are required for the API.
Alex
On 10/11/2012 08:04:58 AM, Alexander Graf wrote:
>
> On 11.10.2012, at 05:32, Tabi Timur-B04825 wrote:
>
> > On Wed, Oct 10, 2012 at 9:47 PM, Stephen Rothwell
> <[email protected]> wrote:
> >
> >> Commit 549d62d889b4 ("KVM: PPC: use definitions in epapr header
> >> for hcalls") from the kvm-ppc tree added an include of
> asm/epapr_hcall.h
> >> to the user visible part of asm/kvm_para.h so asm/epapr_hcall.h
> became a
> >> user visible header file.
> >
> > Any real user-space code that tries to call any of the functions in
> > epapr_hcall.h will cause an exception.
Actually it'll cause a linker error, as of the "Don't use hardcoded
opcode for ePAPR hcall invocation" patch.
> > Claiming that kernel header files that KVM needs are suddenly
> > user-space header files doesn't make much sense to me, but I guess
> > it's not my decision.
>
> This is about kvm_host.h, which is the part that is exported to user
> space. It usually contains constants and structs that are required
> for the API.
s/kvm_host/kvm_para/
I'm not sure anything in kvm_para.h or epapr_hcalls.h would be of use
to userspace, but it would be of use to the guest OS, so it's still not
kernel-internal.
The variable externs should be #ifdef __KERNEL__ as David points out.
The asm stuff could still be useful in a guest OS if the guest provides
epapr_hypercall_start.
-Scott
Alexander Graf wrote:
> This is about kvm_host.h, which is the part that is exported to user
> space. It usually contains constants and structs that are required for
> the API.
Which API? I'm not familiar with KVM internals.
My concern is that when I think of a user-space header file, I think of a
user-space application that calls ioctls. I know that KVM guest kernels
run as user-space processes, but that does not seem like a reason to
combine all of the header files that the KVM guest kernel needs with
"real" user-space header files.
--
Timur Tabi
Linux kernel developer at Freescale
On 11.10.2012, at 17:50, Scott Wood wrote:
> On 10/11/2012 08:04:58 AM, Alexander Graf wrote:
>> On 11.10.2012, at 05:32, Tabi Timur-B04825 wrote:
>> > On Wed, Oct 10, 2012 at 9:47 PM, Stephen Rothwell <[email protected]> wrote:
>> >
>> >> Commit 549d62d889b4 ("KVM: PPC: use definitions in epapr header
>> >> for hcalls") from the kvm-ppc tree added an include of asm/epapr_hcall.h
>> >> to the user visible part of asm/kvm_para.h so asm/epapr_hcall.h became a
>> >> user visible header file.
>> >
>> > Any real user-space code that tries to call any of the functions in
>> > epapr_hcall.h will cause an exception.
>
> Actually it'll cause a linker error, as of the "Don't use hardcoded opcode for ePAPR hcall invocation" patch.
>
>> > Claiming that kernel header files that KVM needs are suddenly
>> > user-space header files doesn't make much sense to me, but I guess
>> > it's not my decision.
>> This is about kvm_host.h, which is the part that is exported to user space. It usually contains constants and structs that are required for the API.
>
> s/kvm_host/kvm_para/
>
> I'm not sure anything in kvm_para.h or epapr_hcalls.h would be of use to userspace, but it would be of use to the guest OS, so it's still not kernel-internal.
>
> The variable externs should be #ifdef __KERNEL__ as David points out. The asm stuff could still be useful in a guest OS if the guest provides epapr_hypercall_start.
I don't think we should worry about guest kernel code potentially having use for this. Let's make the user space headers be great for user space usage, not for guest code usage :).
Alex-
On 10/11/2012 10:56:51 AM, Alexander Graf wrote:
>
> On 11.10.2012, at 17:50, Scott Wood wrote:
>
> > On 10/11/2012 08:04:58 AM, Alexander Graf wrote:
> >> On 11.10.2012, at 05:32, Tabi Timur-B04825 wrote:
> >> > On Wed, Oct 10, 2012 at 9:47 PM, Stephen Rothwell
> <[email protected]> wrote:
> >> >
> >> >> Commit 549d62d889b4 ("KVM: PPC: use definitions in epapr header
> >> >> for hcalls") from the kvm-ppc tree added an include of
> asm/epapr_hcall.h
> >> >> to the user visible part of asm/kvm_para.h so asm/epapr_hcall.h
> became a
> >> >> user visible header file.
> >> >
> >> > Any real user-space code that tries to call any of the functions
> in
> >> > epapr_hcall.h will cause an exception.
> >
> > Actually it'll cause a linker error, as of the "Don't use hardcoded
> opcode for ePAPR hcall invocation" patch.
> >
> >> > Claiming that kernel header files that KVM needs are suddenly
> >> > user-space header files doesn't make much sense to me, but I
> guess
> >> > it's not my decision.
> >> This is about kvm_host.h, which is the part that is exported to
> user space. It usually contains constants and structs that are
> required for the API.
> >
> > s/kvm_host/kvm_para/
> >
> > I'm not sure anything in kvm_para.h or epapr_hcalls.h would be of
> use to userspace, but it would be of use to the guest OS, so it's
> still not kernel-internal.
> >
> > The variable externs should be #ifdef __KERNEL__ as David points
> out. The asm stuff could still be useful in a guest OS if the guest
> provides epapr_hypercall_start.
>
> I don't think we should worry about guest kernel code potentially
> having use for this. Let's make the user space headers be great for
> user space usage, not for guest code usage :).
Well, that asm stuff started out as a guest header (from Freescale's
Topaz hypervisor), not a Linux header. :-)
-Scott
On 10/11/2012 10:55:42 AM, Timur Tabi wrote:
> Alexander Graf wrote:
>
>
> > This is about kvm_host.h, which is the part that is exported to user
> > space. It usually contains constants and structs that are required
> for
> > the API.
>
> Which API? I'm not familiar with KVM internals.
>
> My concern is that when I think of a user-space header file, I think
> of a
> user-space application that calls ioctls. I know that KVM guest
> kernels
> run as user-space processes, but that does not seem like a reason to
> combine all of the header files that the KVM guest kernel needs with
> "real" user-space header files.
So where should guest headers go?
-Scott
Scott Wood wrote:
>> > My concern is that when I think of a user-space header file, I think
>> > of a
>> > user-space application that calls ioctls. I know that KVM guest
>> > kernels
>> > run as user-space processes, but that does not seem like a reason to
>> > combine all of the header files that the KVM guest kernel needs with
>> > "real" user-space header files.
> So where should guest headers go?
I admit that I don't have any answers, especially since this whole thing
is new to me. Like I said, I don't know much about KVM internals, so I
just don't understand why KVM guests need to have access to these kernel
header files as if they're user header files. The guests are still Linux
kernels (or other OSes that think they're running as privileged code).
--
Timur Tabi
Linux kernel developer at Freescale
On 10/11/2012 12:24:59 PM, Timur Tabi wrote:
> Scott Wood wrote:
> >> > My concern is that when I think of a user-space header file, I
> think
> >> > of a
> >> > user-space application that calls ioctls. I know that KVM guest
> >> > kernels
> >> > run as user-space processes, but that does not seem like a
> reason to
> >> > combine all of the header files that the KVM guest kernel needs
> with
> >> > "real" user-space header files.
>
> > So where should guest headers go?
>
> I admit that I don't have any answers, especially since this whole
> thing
> is new to me. Like I said, I don't know much about KVM internals, so
> I
> just don't understand why KVM guests need to have access to these
> kernel
> header files as if they're user header files. The guests are still
> Linux
> kernels (or other OSes that think they're running as privileged code).
For hypercalls and other paravirt. That's the point -- they're not
kernel headers. They're guest API headers.
-scott
Scott Wood wrote:
> For hypercalls and other paravirt. That's the point -- they're not
> kernel headers. They're guest API headers.
Well, IMHO, guest API != user-space. Maybe we should have a parallel
mechanism to uapi to make the kvm guest header files available.
--
Timur Tabi
Linux kernel developer at Freescale