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This patch is a rollup of all the core pieces of the Xen implementation, including: - booting and setup - pagetable setup - privileged instructions - segmentation - interrupt flags - upcalls - multicall batching BOOTING AND SETUP The vmlinux image is decorated with ELF notes which tell the Xen domain builder what the kernel's requirements are; the domain builder then constructs the address space accordingly and starts the kernel. Xen has its own entrypoint for the kernel (contained in an ELF note). The ELF notes are set up by xen-head.S, which is included into head.S. In principle it could be linked separately, but it seems to provoke lots of binutils bugs. Because the domain builder starts the kernel in a fairly sane state (32-bit protected mode, paging enabled, flat segments set up), there's not a lot of setup needed before starting the kernel proper. The main steps are: 1. Install the Xen paravirt_ops, which is simply a matter of a structure assignment. 2. Set init_mm to use the Xen-supplied pagetables (analogous to the head.S generated pagetables in a native boot). 3. Reserve address space for Xen, since it takes a chunk at the top of the address space for its own use. 4. Call start_kernel() PAGETABLE SETUP Once we hit the main kernel boot sequence, it will end up calling back via paravirt_ops to set up various pieces of Xen specific state. One of the critical things which requires a bit of extra care is the construction of the initial init_mm pagetable. Because Xen places tight constraints on pagetables (an active pagetable must always be valid, and must always be mapped read-only to the guest domain), we need to be careful when constructing the new pagetable to keep these constraints in mind. It turns out that the easiest way to do this is use the initial Xen-provided pagetable as a template, and then just insert new mappings for memory where a mapping doesn't already exist. This means that during pagetable setup, it uses a special version of xen_set_pte which ignores any attempt to remap a read-only page as read-write (since Xen will map its own initial pagetable as RO), but lets other changes to the ptes happen, so that things like NX are set properly. PRIVILEGED INSTRUCTIONS AND SEGMENTATION When the kernel runs under Xen, it runs in ring 1 rather than ring 0. This means that it is more privileged than user-mode in ring 3, but it still can't run privileged instructions directly. Non-performance critical instructions are dealt with by taking a privilege exception and trapping into the hypervisor and emulating the instruction, but more performance-critical instructions have their own specific paravirt_ops. In many cases we can avoid having to do any hypercalls for these instructions, or the Xen implementation is quite different from the normal native version. The privileged instructions fall into the broad classes of: Segmentation: setting up the GDT and the GDT entries, LDT, TLS and so on. Xen doesn't allow the GDT to be directly modified; all GDT updates are done via hypercalls where the new entries can be validated. This is important because Xen uses segment limits to prevent the guest kernel from damaging the hypervisor itself. Traps and exceptions: Xen uses a special format for trap entrypoints, so when the kernel wants to set an IDT entry, it needs to be converted to the form Xen expects. Xen sets int 0x80 up specially so that the trap goes straight from userspace into the guest kernel without going via the hypervisor. sysenter isn't supported. Kernel stack: The esp0 entry is extracted from the tss and provided to Xen. TLB operations: the various TLB calls are mapped into corresponding Xen hypercalls. Control registers: all the control registers are privileged. The most important is cr3, which points to the base of the current pagetable, and we handle it specially. Another instruction we treat specially is CPUID, even though its not privileged. We want to control what CPU features are visible to the rest of the kernel, and so CPUID ends up going into a paravirt_op. Xen implements this mainly to disable the ACPI and APIC subsystems. INTERRUPT FLAGS Xen maintains its own separate flag for masking events, which is contained within the per-cpu vcpu_info structure. Because the guest kernel runs in ring 1 and not 0, the IF flag in EFLAGS is completely ignored (and must be, because even if a guest domain disables interrupts for itself, it can't disable them overall). (A note on terminology: "events" and interrupts are effectively synonymous. However, rather than using an "enable flag", Xen uses a "mask flag", which blocks event delivery when it is non-zero.) There are paravirt_ops for each of cli/sti/save_fl/restore_fl, which are implemented to manage the Xen event mask state. The only thing worth noting is that when events are unmasked, we need to explicitly see if there's a pending event and call into the hypervisor to make sure it gets delivered. UPCALLS Xen needs a couple of upcall (or callback) functions to be implemented by each guest. One is the event upcalls, which is how events (interrupts, effectively) are delivered to the guests. The other is the failsafe callback, which is used to report errors in either reloading a segment register, or caused by iret. These are implemented in i386/kernel/entry.S so they can jump into the normal iret_exc path when necessary. MULTICALL BATCHING Xen provides a multicall mechanism, which allows multiple hypercalls to be issued at once in order to mitigate the cost of trapping into the hypervisor. This is particularly useful for context switches, since the 4-5 hypercalls they would normally need (reload cr3, update TLS, maybe update LDT) can be reduced to one. This patch implements a generic batching mechanism for hypercalls, which gets used in many places in the Xen code. Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Cc: Ian Pratt <ian.pratt@xensource.com> Cc: Christian Limpach <Christian.Limpach@cl.cam.ac.uk> Cc: Adrian Bunk <bunk@stusta.de>
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obj-y := enlighten.o setup.o features.o multicalls.o |
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/****************************************************************************** | ||
* features.c | ||
* | ||
* Xen feature flags. | ||
* | ||
* Copyright (c) 2006, Ian Campbell, XenSource Inc. | ||
*/ | ||
#include <linux/types.h> | ||
#include <linux/cache.h> | ||
#include <linux/module.h> | ||
#include <asm/xen/hypervisor.h> | ||
#include <xen/features.h> | ||
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u8 xen_features[XENFEAT_NR_SUBMAPS * 32] __read_mostly; | ||
EXPORT_SYMBOL_GPL(xen_features); | ||
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void xen_setup_features(void) | ||
{ | ||
struct xen_feature_info fi; | ||
int i, j; | ||
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for (i = 0; i < XENFEAT_NR_SUBMAPS; i++) { | ||
fi.submap_idx = i; | ||
if (HYPERVISOR_xen_version(XENVER_get_features, &fi) < 0) | ||
break; | ||
for (j = 0; j < 32; j++) | ||
xen_features[i * 32 + j] = !!(fi.submap & 1<<j); | ||
} | ||
} |
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/* | ||
* Xen hypercall batching. | ||
* | ||
* Xen allows multiple hypercalls to be issued at once, using the | ||
* multicall interface. This allows the cost of trapping into the | ||
* hypervisor to be amortized over several calls. | ||
* | ||
* This file implements a simple interface for multicalls. There's a | ||
* per-cpu buffer of outstanding multicalls. When you want to queue a | ||
* multicall for issuing, you can allocate a multicall slot for the | ||
* call and its arguments, along with storage for space which is | ||
* pointed to by the arguments (for passing pointers to structures, | ||
* etc). When the multicall is actually issued, all the space for the | ||
* commands and allocated memory is freed for reuse. | ||
* | ||
* Multicalls are flushed whenever any of the buffers get full, or | ||
* when explicitly requested. There's no way to get per-multicall | ||
* return results back. It will BUG if any of the multicalls fail. | ||
* | ||
* Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007 | ||
*/ | ||
#include <linux/percpu.h> | ||
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#include <asm/xen/hypercall.h> | ||
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#include "multicalls.h" | ||
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#define MC_BATCH 8 | ||
#define MC_ARGS (MC_BATCH * 32 / sizeof(u64)) | ||
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struct mc_buffer { | ||
struct multicall_entry entries[MC_BATCH]; | ||
u64 args[MC_ARGS]; | ||
unsigned mcidx, argidx; | ||
}; | ||
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static DEFINE_PER_CPU(struct mc_buffer, mc_buffer); | ||
DEFINE_PER_CPU(unsigned long, xen_mc_irq_flags); | ||
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void xen_mc_flush(void) | ||
{ | ||
struct mc_buffer *b = &get_cpu_var(mc_buffer); | ||
int ret = 0; | ||
unsigned long flags; | ||
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/* Disable interrupts in case someone comes in and queues | ||
something in the middle */ | ||
local_irq_save(flags); | ||
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if (b->mcidx) { | ||
int i; | ||
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if (HYPERVISOR_multicall(b->entries, b->mcidx) != 0) | ||
BUG(); | ||
for (i = 0; i < b->mcidx; i++) | ||
if (b->entries[i].result < 0) | ||
ret++; | ||
b->mcidx = 0; | ||
b->argidx = 0; | ||
} else | ||
BUG_ON(b->argidx != 0); | ||
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put_cpu_var(mc_buffer); | ||
local_irq_restore(flags); | ||
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BUG_ON(ret); | ||
} | ||
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struct multicall_space __xen_mc_entry(size_t args) | ||
{ | ||
struct mc_buffer *b = &get_cpu_var(mc_buffer); | ||
struct multicall_space ret; | ||
unsigned argspace = (args + sizeof(u64) - 1) / sizeof(u64); | ||
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BUG_ON(argspace > MC_ARGS); | ||
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if (b->mcidx == MC_BATCH || | ||
(b->argidx + argspace) > MC_ARGS) | ||
xen_mc_flush(); | ||
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ret.mc = &b->entries[b->mcidx]; | ||
b->mcidx++; | ||
ret.args = &b->args[b->argidx]; | ||
b->argidx += argspace; | ||
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put_cpu_var(mc_buffer); | ||
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return ret; | ||
} |
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#ifndef _XEN_MULTICALLS_H | ||
#define _XEN_MULTICALLS_H | ||
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#include "xen-ops.h" | ||
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/* Multicalls */ | ||
struct multicall_space | ||
{ | ||
struct multicall_entry *mc; | ||
void *args; | ||
}; | ||
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/* Allocate room for a multicall and its args */ | ||
struct multicall_space __xen_mc_entry(size_t args); | ||
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DECLARE_PER_CPU(unsigned long, xen_mc_irq_flags); | ||
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/* Call to start a batch of multiple __xen_mc_entry()s. Must be | ||
paired with xen_mc_issue() */ | ||
static inline void xen_mc_batch(void) | ||
{ | ||
/* need to disable interrupts until this entry is complete */ | ||
local_irq_save(__get_cpu_var(xen_mc_irq_flags)); | ||
} | ||
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static inline struct multicall_space xen_mc_entry(size_t args) | ||
{ | ||
xen_mc_batch(); | ||
return __xen_mc_entry(args); | ||
} | ||
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/* Flush all pending multicalls */ | ||
void xen_mc_flush(void); | ||
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/* Issue a multicall if we're not in a lazy mode */ | ||
static inline void xen_mc_issue(unsigned mode) | ||
{ | ||
if ((xen_get_lazy_mode() & mode) == 0) | ||
xen_mc_flush(); | ||
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/* restore flags saved in xen_mc_batch */ | ||
local_irq_restore(x86_read_percpu(xen_mc_irq_flags)); | ||
} | ||
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#endif /* _XEN_MULTICALLS_H */ |
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/* | ||
* Machine specific setup for xen | ||
* | ||
* Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007 | ||
*/ | ||
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#include <linux/module.h> | ||
#include <linux/sched.h> | ||
#include <linux/mm.h> | ||
#include <linux/pm.h> | ||
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#include <asm/elf.h> | ||
#include <asm/e820.h> | ||
#include <asm/setup.h> | ||
#include <asm/xen/hypervisor.h> | ||
#include <asm/xen/hypercall.h> | ||
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#include <xen/interface/physdev.h> | ||
#include <xen/features.h> | ||
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#include "xen-ops.h" | ||
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/* These are code, but not functions. Defined in entry.S */ | ||
extern const char xen_hypervisor_callback[]; | ||
extern const char xen_failsafe_callback[]; | ||
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static __initdata struct shared_info init_shared; | ||
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/* | ||
* Point at some empty memory to start with. We map the real shared_info | ||
* page as soon as fixmap is up and running. | ||
*/ | ||
struct shared_info *HYPERVISOR_shared_info = &init_shared; | ||
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unsigned long *phys_to_machine_mapping; | ||
EXPORT_SYMBOL(phys_to_machine_mapping); | ||
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/** | ||
* machine_specific_memory_setup - Hook for machine specific memory setup. | ||
**/ | ||
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char * __init xen_memory_setup(void) | ||
{ | ||
unsigned long max_pfn = xen_start_info->nr_pages; | ||
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e820.nr_map = 0; | ||
add_memory_region(0, PFN_PHYS(max_pfn), E820_RAM); | ||
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return "Xen"; | ||
} | ||
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static void xen_idle(void) | ||
{ | ||
local_irq_disable(); | ||
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if (need_resched()) | ||
local_irq_enable(); | ||
else { | ||
current_thread_info()->status &= ~TS_POLLING; | ||
smp_mb__after_clear_bit(); | ||
safe_halt(); | ||
current_thread_info()->status |= TS_POLLING; | ||
} | ||
} | ||
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void __init xen_arch_setup(void) | ||
{ | ||
struct physdev_set_iopl set_iopl; | ||
int rc; | ||
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HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments); | ||
HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables); | ||
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if (!xen_feature(XENFEAT_auto_translated_physmap)) | ||
HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_pae_extended_cr3); | ||
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HYPERVISOR_set_callbacks(__KERNEL_CS, (unsigned long)xen_hypervisor_callback, | ||
__KERNEL_CS, (unsigned long)xen_failsafe_callback); | ||
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set_iopl.iopl = 1; | ||
rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl); | ||
if (rc != 0) | ||
printk(KERN_INFO "physdev_op failed %d\n", rc); | ||
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#ifdef CONFIG_ACPI | ||
if (!(xen_start_info->flags & SIF_INITDOMAIN)) { | ||
printk(KERN_INFO "ACPI in unprivileged domain disabled\n"); | ||
disable_acpi(); | ||
} | ||
#endif | ||
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memcpy(boot_command_line, xen_start_info->cmd_line, | ||
MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ? | ||
COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE); | ||
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pm_idle = xen_idle; | ||
} |
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/* Xen-specific pieces of head.S, intended to be included in the right | ||
place in head.S */ | ||
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#ifdef CONFIG_XEN | ||
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#include <linux/elfnote.h> | ||
#include <asm/boot.h> | ||
#include <xen/interface/elfnote.h> | ||
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ENTRY(startup_xen) | ||
movl %esi,xen_start_info | ||
cld | ||
movl $(init_thread_union+THREAD_SIZE),%esp | ||
jmp xen_start_kernel | ||
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.pushsection ".bss.page_aligned" | ||
.align PAGE_SIZE_asm | ||
ENTRY(hypercall_page) | ||
.skip 0x1000 | ||
.popsection | ||
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ELFNOTE(Xen, XEN_ELFNOTE_GUEST_OS, .asciz "linux") | ||
ELFNOTE(Xen, XEN_ELFNOTE_GUEST_VERSION, .asciz "2.6") | ||
ELFNOTE(Xen, XEN_ELFNOTE_XEN_VERSION, .asciz "xen-3.0") | ||
ELFNOTE(Xen, XEN_ELFNOTE_VIRT_BASE, .long __PAGE_OFFSET) | ||
ELFNOTE(Xen, XEN_ELFNOTE_ENTRY, .long startup_xen) | ||
ELFNOTE(Xen, XEN_ELFNOTE_HYPERCALL_PAGE, .long hypercall_page) | ||
ELFNOTE(Xen, XEN_ELFNOTE_FEATURES, .asciz "!writable_page_tables|pae_pgdir_above_4gb") | ||
#ifdef CONFIG_X86_PAE | ||
ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE, .asciz "yes") | ||
#else | ||
ELFNOTE(Xen, XEN_ELFNOTE_PAE_MODE, .asciz "no") | ||
#endif | ||
ELFNOTE(Xen, XEN_ELFNOTE_LOADER, .asciz "generic") | ||
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#endif /*CONFIG_XEN */ |
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#ifndef XEN_OPS_H | ||
#define XEN_OPS_H | ||
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#include <linux/init.h> | ||
#include <linux/clocksource.h> | ||
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DECLARE_PER_CPU(struct vcpu_info *, xen_vcpu); | ||
DECLARE_PER_CPU(unsigned long, xen_cr3); | ||
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extern struct start_info *xen_start_info; | ||
extern struct shared_info *HYPERVISOR_shared_info; | ||
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char * __init xen_memory_setup(void); | ||
void __init xen_arch_setup(void); | ||
void __init xen_init_IRQ(void); | ||
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unsigned long xen_cpu_khz(void); | ||
void __init xen_time_init(void); | ||
unsigned long xen_get_wallclock(void); | ||
int xen_set_wallclock(unsigned long time); | ||
cycle_t xen_clocksource_read(void); | ||
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DECLARE_PER_CPU(enum paravirt_lazy_mode, xen_lazy_mode); | ||
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static inline unsigned xen_get_lazy_mode(void) | ||
{ | ||
return x86_read_percpu(xen_lazy_mode); | ||
} | ||
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#endif /* XEN_OPS_H */ |
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/****************************************************************************** | ||
* features.h | ||
* | ||
* Query the features reported by Xen. | ||
* | ||
* Copyright (c) 2006, Ian Campbell | ||
*/ | ||
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#ifndef __XEN_FEATURES_H__ | ||
#define __XEN_FEATURES_H__ | ||
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#include <xen/interface/features.h> | ||
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void xen_setup_features(void); | ||
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extern u8 xen_features[XENFEAT_NR_SUBMAPS * 32]; | ||
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static inline int xen_feature(int flag) | ||
{ | ||
return xen_features[flag]; | ||
} | ||
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#endif /* __ASM_XEN_FEATURES_H__ */ |
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#ifndef __XEN_PAGE_H | ||
#define __XEN_PAGE_H | ||
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#include <linux/pfn.h> | ||
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#include <asm/uaccess.h> | ||
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#include <xen/features.h> | ||
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#ifdef CONFIG_X86_PAE | ||
/* Xen machine address */ | ||
typedef struct xmaddr { | ||
unsigned long long maddr; | ||
} xmaddr_t; | ||
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/* Xen pseudo-physical address */ | ||
typedef struct xpaddr { | ||
unsigned long long paddr; | ||
} xpaddr_t; | ||
#else | ||
/* Xen machine address */ | ||
typedef struct xmaddr { | ||
unsigned long maddr; | ||
} xmaddr_t; | ||
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/* Xen pseudo-physical address */ | ||
typedef struct xpaddr { | ||
unsigned long paddr; | ||
} xpaddr_t; | ||
#endif | ||
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#define XMADDR(x) ((xmaddr_t) { .maddr = (x) }) | ||
#define XPADDR(x) ((xpaddr_t) { .paddr = (x) }) | ||
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/**** MACHINE <-> PHYSICAL CONVERSION MACROS ****/ | ||
#define INVALID_P2M_ENTRY (~0UL) | ||
#define FOREIGN_FRAME_BIT (1UL<<31) | ||
#define FOREIGN_FRAME(m) ((m) | FOREIGN_FRAME_BIT) | ||
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extern unsigned long *phys_to_machine_mapping; | ||
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static inline unsigned long pfn_to_mfn(unsigned long pfn) | ||
{ | ||
if (xen_feature(XENFEAT_auto_translated_physmap)) | ||
return pfn; | ||
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return phys_to_machine_mapping[(unsigned int)(pfn)] & | ||
~FOREIGN_FRAME_BIT; | ||
} | ||
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static inline int phys_to_machine_mapping_valid(unsigned long pfn) | ||
{ | ||
if (xen_feature(XENFEAT_auto_translated_physmap)) | ||
return 1; | ||
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return (phys_to_machine_mapping[pfn] != INVALID_P2M_ENTRY); | ||
} | ||
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static inline unsigned long mfn_to_pfn(unsigned long mfn) | ||
{ | ||
unsigned long pfn; | ||
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if (xen_feature(XENFEAT_auto_translated_physmap)) | ||
return mfn; | ||
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#if 0 | ||
if (unlikely((mfn >> machine_to_phys_order) != 0)) | ||
return max_mapnr; | ||
#endif | ||
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pfn = 0; | ||
/* | ||
* The array access can fail (e.g., device space beyond end of RAM). | ||
* In such cases it doesn't matter what we return (we return garbage), | ||
* but we must handle the fault without crashing! | ||
*/ | ||
__get_user(pfn, &machine_to_phys_mapping[mfn]); | ||
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return pfn; | ||
} | ||
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static inline xmaddr_t phys_to_machine(xpaddr_t phys) | ||
{ | ||
unsigned offset = phys.paddr & ~PAGE_MASK; | ||
return XMADDR(PFN_PHYS((u64)pfn_to_mfn(PFN_DOWN(phys.paddr))) | offset); | ||
} | ||
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static inline xpaddr_t machine_to_phys(xmaddr_t machine) | ||
{ | ||
unsigned offset = machine.maddr & ~PAGE_MASK; | ||
return XPADDR(PFN_PHYS((u64)mfn_to_pfn(PFN_DOWN(machine.maddr))) | offset); | ||
} | ||
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/* | ||
* We detect special mappings in one of two ways: | ||
* 1. If the MFN is an I/O page then Xen will set the m2p entry | ||
* to be outside our maximum possible pseudophys range. | ||
* 2. If the MFN belongs to a different domain then we will certainly | ||
* not have MFN in our p2m table. Conversely, if the page is ours, | ||
* then we'll have p2m(m2p(MFN))==MFN. | ||
* If we detect a special mapping then it doesn't have a 'struct page'. | ||
* We force !pfn_valid() by returning an out-of-range pointer. | ||
* | ||
* NB. These checks require that, for any MFN that is not in our reservation, | ||
* there is no PFN such that p2m(PFN) == MFN. Otherwise we can get confused if | ||
* we are foreign-mapping the MFN, and the other domain as m2p(MFN) == PFN. | ||
* Yikes! Various places must poke in INVALID_P2M_ENTRY for safety. | ||
* | ||
* NB2. When deliberately mapping foreign pages into the p2m table, you *must* | ||
* use FOREIGN_FRAME(). This will cause pte_pfn() to choke on it, as we | ||
* require. In all the cases we care about, the FOREIGN_FRAME bit is | ||
* masked (e.g., pfn_to_mfn()) so behaviour there is correct. | ||
*/ | ||
static inline unsigned long mfn_to_local_pfn(unsigned long mfn) | ||
{ | ||
extern unsigned long max_mapnr; | ||
unsigned long pfn = mfn_to_pfn(mfn); | ||
if ((pfn < max_mapnr) | ||
&& !xen_feature(XENFEAT_auto_translated_physmap) | ||
&& (phys_to_machine_mapping[pfn] != mfn)) | ||
return max_mapnr; /* force !pfn_valid() */ | ||
return pfn; | ||
} | ||
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static inline void set_phys_to_machine(unsigned long pfn, unsigned long mfn) | ||
{ | ||
if (xen_feature(XENFEAT_auto_translated_physmap)) { | ||
BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY); | ||
return; | ||
} | ||
phys_to_machine_mapping[pfn] = mfn; | ||
} | ||
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/* VIRT <-> MACHINE conversion */ | ||
#define virt_to_machine(v) (phys_to_machine(XPADDR(__pa(v)))) | ||
#define virt_to_mfn(v) (pfn_to_mfn(PFN_DOWN(__pa(v)))) | ||
#define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT)) | ||
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#ifdef CONFIG_X86_PAE | ||
#define pte_mfn(_pte) (((_pte).pte_low >> PAGE_SHIFT) | \ | ||
(((_pte).pte_high & 0xfff) << (32-PAGE_SHIFT))) | ||
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static inline pte_t mfn_pte(unsigned long page_nr, pgprot_t pgprot) | ||
{ | ||
pte_t pte; | ||
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pte.pte_high = (page_nr >> (32 - PAGE_SHIFT)) | | ||
(pgprot_val(pgprot) >> 32); | ||
pte.pte_high &= (__supported_pte_mask >> 32); | ||
pte.pte_low = ((page_nr << PAGE_SHIFT) | pgprot_val(pgprot)); | ||
pte.pte_low &= __supported_pte_mask; | ||
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return pte; | ||
} | ||
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static inline unsigned long long pte_val_ma(pte_t x) | ||
{ | ||
return ((unsigned long long)x.pte_high << 32) | x.pte_low; | ||
} | ||
#define pmd_val_ma(v) ((v).pmd) | ||
#define pud_val_ma(v) ((v).pgd.pgd) | ||
#define __pte_ma(x) ((pte_t) { .pte_low = (x), .pte_high = (x)>>32 } ) | ||
#define __pmd_ma(x) ((pmd_t) { (x) } ) | ||
#else /* !X86_PAE */ | ||
#define pte_mfn(_pte) ((_pte).pte_low >> PAGE_SHIFT) | ||
#define mfn_pte(pfn, prot) __pte_ma(((pfn) << PAGE_SHIFT) | pgprot_val(prot)) | ||
#define pte_val_ma(x) ((x).pte_low) | ||
#define pmd_val_ma(v) ((v).pud.pgd.pgd) | ||
#define __pte_ma(x) ((pte_t) { (x) } ) | ||
#endif /* CONFIG_X86_PAE */ | ||
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#define pgd_val_ma(x) ((x).pgd) | ||
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xmaddr_t arbitrary_virt_to_machine(unsigned long address); | ||
void make_lowmem_page_readonly(void *vaddr); | ||
void make_lowmem_page_readwrite(void *vaddr); | ||
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#endif /* __XEN_PAGE_H */ |