From: Jan Kiszka <jan.kiszka@siemens.com>
Date: Sun, 6 Jul 2014 09:06:07 +0000 (+0200)
Subject: x86: Provide PM timer access to all cells
X-Git-Url: https://rtime.felk.cvut.cz/gitweb/jailhouse.git/commitdiff_plain/cebf6a2cd83da41bc7a245bfb09de207660db026

x86: Provide PM timer access to all cells

Export the PM timer address via the Communication Region to non-root
cells and allow access to that port for all cells. This is safe as the
PM timer hardware is specified to be read-only.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---

diff --git a/Documentation/hypervisor-interfaces.txt b/Documentation/hypervisor-interfaces.txt
index 82cd6b5..6726e45 100644
--- a/Documentation/hypervisor-interfaces.txt
+++ b/Documentation/hypervisor-interfaces.txt
@@ -228,9 +228,16 @@ Communication region layout
         |  Message from Cell (32 bit)  |
         +------------------------------+
         |     Cell State (32 bit)      |
+        +------------------------------+
+        |      Reserved (32 bit)       |
+        +------------------------------+
+        :     Platform Information     :
         +------------------------------+ - higher address
 
-All fields use the native endianness of the system.
+All fields use the native endianness of the system. The format is of the
+Platform Information part is architecture-specific. Its content is filled by
+the hypervisor during cell creation and shall be considered read-only until
+cell destruction.
 
 
 Logical Channel "Message"
@@ -307,6 +314,16 @@ to destroy or restart that cell. On restart, it will also reset the state field
 to "Running".
 
 
+Platform Information for x86
+- - - - - - - - - - - - - - -
+
+        +------------------------------+ - begin of communication region
+        :   generic part, see above    :   (lower address)
+        +------------------------------+
+        |   PM Timer Address (16 bit)  |
+        +------------------------------+ - higher address
+
+
 References
 ----------
 
diff --git a/hypervisor/arch/arm/include/asm/jailhouse_hypercall.h b/hypervisor/arch/arm/include/asm/jailhouse_hypercall.h
index 7a07f27..1967138 100644
--- a/hypervisor/arch/arm/include/asm/jailhouse_hypercall.h
+++ b/hypervisor/arch/arm/include/asm/jailhouse_hypercall.h
@@ -27,6 +27,10 @@
 
 #ifndef __ASSEMBLY__
 
+struct jailhouse_comm_region {
+	COMM_REGION_GENERIC_HEADER;
+};
+
 static inline __u32 jailhouse_call(__u32 num)
 {
 	register __u32 num_result asm(JAILHOUSE_CALL_NUM_RESULT) = num;
diff --git a/hypervisor/arch/x86/control.c b/hypervisor/arch/x86/control.c
index d4efa1a..5d3468d 100644
--- a/hypervisor/arch/x86/control.c
+++ b/hypervisor/arch/x86/control.c
@@ -44,6 +44,9 @@ int arch_cell_create(struct per_cpu *cpu_data, struct cell *cell)
 	ioapic_cell_init(cell);
 	ioapic_root_cell_shrink(cell->config);
 
+	cell->comm_page.comm_region.pm_timer_address =
+		system_config->platform_info.x86.pm_timer_address;
+
 	return 0;
 }
 
diff --git a/hypervisor/arch/x86/include/asm/jailhouse_hypercall.h b/hypervisor/arch/x86/include/asm/jailhouse_hypercall.h
index 9145e6e..54cd228 100644
--- a/hypervisor/arch/x86/include/asm/jailhouse_hypercall.h
+++ b/hypervisor/arch/x86/include/asm/jailhouse_hypercall.h
@@ -33,6 +33,12 @@
 
 #ifndef __ASSEMBLY__
 
+struct jailhouse_comm_region {
+	COMM_REGION_GENERIC_HEADER;
+
+	__u16 pm_timer_address;
+};
+
 static inline __u32 jailhouse_call(__u32 num)
 {
 	__u32 result;
diff --git a/hypervisor/arch/x86/vmx.c b/hypervisor/arch/x86/vmx.c
index d6172e6..e6b97a7 100644
--- a/hypervisor/arch/x86/vmx.c
+++ b/hypervisor/arch/x86/vmx.c
@@ -259,10 +259,15 @@ int vmx_cell_init(struct cell *cell)
 {
 	const u8 *pio_bitmap = jailhouse_cell_pio_bitmap(cell->config);
 	u32 pio_bitmap_size = cell->config->pio_bitmap_size;
-	int n, err;
+	unsigned int n, pm_timer_addr;
 	u32 size;
+	int err;
 	u8 *b;
 
+	/* PM timer has to be provided */
+	if (system_config->platform_info.x86.pm_timer_address == 0)
+		return -EINVAL;
+
 	/* build root EPT of cell */
 	cell->vmx.ept_structs.root_paging = ept_paging;
 	cell->vmx.ept_structs.root_table = page_alloc(&mem_pool, 1);
@@ -301,6 +306,13 @@ int vmx_cell_init(struct cell *cell)
 			*b |= ~*pio_bitmap;
 	}
 
+	/* permit access to the PM timer */
+	pm_timer_addr = system_config->platform_info.x86.pm_timer_address;
+	for (n = 0; n < 4; n++, pm_timer_addr++) {
+		b = cell->vmx.io_bitmap;
+		b[pm_timer_addr / 8] &= ~(1 << (pm_timer_addr % 8));
+	}
+
 	return 0;
 }
 
diff --git a/hypervisor/include/jailhouse/hypercall.h b/hypervisor/include/jailhouse/hypercall.h
index 9cbc807..072874d 100644
--- a/hypervisor/include/jailhouse/hypercall.h
+++ b/hypervisor/include/jailhouse/hypercall.h
@@ -62,18 +62,11 @@
 #define JAILHOUSE_CELL_SHUT_DOWN		2 /* terminal state */
 #define JAILHOUSE_CELL_FAILED			3 /* terminal state */
 
-#ifndef __ASSEMBLY__
-
-struct jailhouse_comm_region {
-	volatile __u32 msg_to_cell;
-	volatile __u32 reply_from_cell;
-
-	volatile __u32 cell_state;
-
-	/* errors etc. */
-};
-
-#endif /* !__ASSEMBLY__ */
+#define COMM_REGION_GENERIC_HEADER		\
+	volatile __u32 msg_to_cell;		\
+	volatile __u32 reply_from_cell;		\
+	volatile __u32 cell_state;		\
+	volatile __u32 padding
 
 #include <asm/jailhouse_hypercall.h>