From: Gleb Natapov <gleb@redhat.com>
To: kvm@vger.kernel.org
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: [PATCH 02/11] Add "handle page fault" PV helper.
Date: Sun, 1 Nov 2009 13:56:21 +0200 [thread overview]
Message-ID: <1257076590-29559-3-git-send-email-gleb@redhat.com> (raw)
In-Reply-To: <1257076590-29559-1-git-send-email-gleb@redhat.com>
Allow paravirtualized guest to do special handling for some page faults.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
---
arch/x86/include/asm/paravirt.h | 7 +++++++
arch/x86/include/asm/paravirt_types.h | 4 ++++
arch/x86/kernel/paravirt.c | 8 ++++++++
arch/x86/kernel/paravirt_patch_32.c | 8 ++++++++
arch/x86/kernel/paravirt_patch_64.c | 7 +++++++
arch/x86/mm/fault.c | 3 +++
6 files changed, 37 insertions(+), 0 deletions(-)
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index efb3899..5203da1 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -6,6 +6,7 @@
#ifdef CONFIG_PARAVIRT
#include <asm/pgtable_types.h>
#include <asm/asm.h>
+#include <asm/ptrace.h>
#include <asm/paravirt_types.h>
@@ -710,6 +711,12 @@ static inline void arch_end_context_switch(struct task_struct *next)
PVOP_VCALL1(pv_cpu_ops.end_context_switch, next);
}
+static inline int arch_handle_page_fault(struct pt_regs *regs,
+ unsigned long error_code)
+{
+ return PVOP_CALL2(int, pv_cpu_ops.handle_pf, regs, error_code);
+}
+
#define __HAVE_ARCH_ENTER_LAZY_MMU_MODE
static inline void arch_enter_lazy_mmu_mode(void)
{
diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index 9357473..bcc39b3 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -186,6 +186,7 @@ struct pv_cpu_ops {
void (*start_context_switch)(struct task_struct *prev);
void (*end_context_switch)(struct task_struct *next);
+ int (*handle_pf)(struct pt_regs *regs, unsigned long error_code);
};
struct pv_irq_ops {
@@ -385,6 +386,7 @@ extern struct pv_lock_ops pv_lock_ops;
unsigned paravirt_patch_nop(void);
unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len);
unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len);
+unsigned paravirt_patch_ret_0(void *insnbuf, unsigned len);
unsigned paravirt_patch_ignore(unsigned len);
unsigned paravirt_patch_call(void *insnbuf,
const void *target, u16 tgt_clobbers,
@@ -676,8 +678,10 @@ void paravirt_leave_lazy_mmu(void);
void _paravirt_nop(void);
u32 _paravirt_ident_32(u32);
u64 _paravirt_ident_64(u64);
+unsigned long _paravirt_ret_0(void);
#define paravirt_nop ((void *)_paravirt_nop)
+#define paravirt_ret_0 ((void *)_paravirt_ret_0)
/* These all sit in the .parainstructions section to tell us what to patch. */
struct paravirt_patch_site {
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index 1b1739d..7d8f37b 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -54,6 +54,11 @@ u64 _paravirt_ident_64(u64 x)
return x;
}
+unsigned long _paravirt_ret_0(void)
+{
+ return 0;
+}
+
void __init default_banner(void)
{
printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
@@ -154,6 +159,8 @@ unsigned paravirt_patch_default(u8 type, u16 clobbers, void *insnbuf,
ret = paravirt_patch_ident_32(insnbuf, len);
else if (opfunc == _paravirt_ident_64)
ret = paravirt_patch_ident_64(insnbuf, len);
+ else if (opfunc == _paravirt_ret_0)
+ ret = paravirt_patch_ret_0(insnbuf, len);
else if (type == PARAVIRT_PATCH(pv_cpu_ops.iret) ||
type == PARAVIRT_PATCH(pv_cpu_ops.irq_enable_sysexit) ||
@@ -380,6 +387,7 @@ struct pv_cpu_ops pv_cpu_ops = {
.start_context_switch = paravirt_nop,
.end_context_switch = paravirt_nop,
+ .handle_pf = paravirt_ret_0,
};
struct pv_apic_ops pv_apic_ops = {
diff --git a/arch/x86/kernel/paravirt_patch_32.c b/arch/x86/kernel/paravirt_patch_32.c
index d9f32e6..de006b1 100644
--- a/arch/x86/kernel/paravirt_patch_32.c
+++ b/arch/x86/kernel/paravirt_patch_32.c
@@ -12,6 +12,8 @@ DEF_NATIVE(pv_mmu_ops, read_cr3, "mov %cr3, %eax");
DEF_NATIVE(pv_cpu_ops, clts, "clts");
DEF_NATIVE(pv_cpu_ops, read_tsc, "rdtsc");
+DEF_NATIVE(, mov0, "xor %eax, %eax");
+
unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len)
{
/* arg in %eax, return in %eax */
@@ -24,6 +26,12 @@ unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len)
return 0;
}
+unsigned paravirt_patch_ret_0(void *insnbuf, unsigned len)
+{
+ return paravirt_patch_insns(insnbuf, len,
+ start__mov0, end__mov0);
+}
+
unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
unsigned long addr, unsigned len)
{
diff --git a/arch/x86/kernel/paravirt_patch_64.c b/arch/x86/kernel/paravirt_patch_64.c
index 3f08f34..d685e7d 100644
--- a/arch/x86/kernel/paravirt_patch_64.c
+++ b/arch/x86/kernel/paravirt_patch_64.c
@@ -21,6 +21,7 @@ DEF_NATIVE(pv_cpu_ops, swapgs, "swapgs");
DEF_NATIVE(, mov32, "mov %edi, %eax");
DEF_NATIVE(, mov64, "mov %rdi, %rax");
+DEF_NATIVE(, mov0, "xor %rax, %rax");
unsigned paravirt_patch_ident_32(void *insnbuf, unsigned len)
{
@@ -34,6 +35,12 @@ unsigned paravirt_patch_ident_64(void *insnbuf, unsigned len)
start__mov64, end__mov64);
}
+unsigned paravirt_patch_ret_0(void *insnbuf, unsigned len)
+{
+ return paravirt_patch_insns(insnbuf, len,
+ start__mov0, end__mov0);
+}
+
unsigned native_patch(u8 type, u16 clobbers, void *ibuf,
unsigned long addr, unsigned len)
{
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index f4cee90..14707dc 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -952,6 +952,9 @@ do_page_fault(struct pt_regs *regs, unsigned long error_code)
int write;
int fault;
+ if (arch_handle_page_fault(regs, error_code))
+ return;
+
tsk = current;
mm = tsk->mm;
--
1.6.3.3
next prev parent reply other threads:[~2009-11-01 11:58 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-11-01 11:56 [PATCH 00/11] KVM: Add asynchronous page fault for PV guest Gleb Natapov
2009-11-01 11:56 ` [PATCH 01/11] Add shared memory hypercall to PV Linux guest Gleb Natapov
2009-11-02 4:27 ` Rik van Riel
2009-11-02 7:07 ` Gleb Natapov
2009-11-02 12:18 ` Avi Kivity
2009-11-02 16:18 ` Gleb Natapov
2009-11-03 5:15 ` Avi Kivity
2009-11-03 7:16 ` Gleb Natapov
2009-11-03 7:40 ` Avi Kivity
2009-11-01 11:56 ` Gleb Natapov [this message]
2009-11-02 9:22 ` [PATCH 02/11] Add "handle page fault" PV helper Ingo Molnar
2009-11-02 16:04 ` Gleb Natapov
2009-11-02 16:12 ` Ingo Molnar
2009-11-02 16:22 ` Gleb Natapov
2009-11-02 16:29 ` Ingo Molnar
2009-11-02 16:31 ` Gleb Natapov
2009-11-02 17:42 ` Gleb Natapov
2009-11-08 11:36 ` Ingo Molnar
2009-11-08 12:43 ` Avi Kivity
2009-11-08 12:51 ` Ingo Molnar
2009-11-08 13:01 ` Avi Kivity
2009-11-08 13:05 ` Ingo Molnar
2009-11-08 13:08 ` Avi Kivity
2009-11-08 16:44 ` H. Peter Anvin
2009-11-08 16:47 ` Ingo Molnar
2009-11-02 19:03 ` Rik van Riel
2009-11-02 19:33 ` Avi Kivity
2009-11-02 23:35 ` Rik van Riel
2009-11-03 4:57 ` Avi Kivity
2009-11-05 6:44 ` Tian, Kevin
2009-11-05 8:22 ` Avi Kivity
2009-11-01 11:56 ` [PATCH 03/11] Handle asynchronous page fault in a PV guest Gleb Natapov
2009-11-02 12:38 ` Avi Kivity
2009-11-02 15:54 ` Gleb Natapov
2009-11-03 14:14 ` Marcelo Tosatti
2009-11-03 14:25 ` Gleb Natapov
2009-11-03 14:32 ` Marcelo Tosatti
2009-11-03 14:38 ` Avi Kivity
2009-11-01 11:56 ` [PATCH 04/11] Export __get_user_pages_fast Gleb Natapov
2009-11-02 9:23 ` Ingo Molnar
2009-11-01 11:56 ` [PATCH 05/11] Add get_user_pages() variant that fails if major fault is required Gleb Natapov
2009-11-02 19:05 ` Rik van Riel
2009-11-01 11:56 ` [PATCH 06/11] Inject asynchronous page fault into a guest if page is swapped out Gleb Natapov
2009-11-02 12:56 ` Avi Kivity
2009-11-02 15:41 ` Gleb Natapov
2009-11-01 11:56 ` [PATCH 07/11] Retry fault before vmentry Gleb Natapov
2009-11-02 13:03 ` Avi Kivity
2009-11-01 11:56 ` [PATCH 08/11] Add "wait for page" hypercall Gleb Natapov
2009-11-02 13:05 ` Avi Kivity
2009-11-02 15:13 ` Gleb Natapov
2009-11-02 15:19 ` Avi Kivity
2009-11-01 11:56 ` [PATCH 09/11] Maintain preemptability count even for !CONFIG_PREEMPT kernels Gleb Natapov
2009-11-02 9:24 ` Ingo Molnar
2009-11-01 11:56 ` [PATCH 10/11] Handle async PF in non preemptable context Gleb Natapov
2009-11-01 11:56 ` [PATCH 11/11] Send async PF when guest is not in userspace too Gleb Natapov
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