2 * Machine specific setup for xen
4 * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
7 #include <linux/module.h>
8 #include <linux/sched.h>
15 #include <asm/setup.h>
17 #include <asm/xen/hypervisor.h>
18 #include <asm/xen/hypercall.h>
21 #include <xen/interface/callback.h>
22 #include <xen/interface/physdev.h>
23 #include <xen/interface/memory.h>
24 #include <xen/features.h>
29 /* These are code, but not functions. Defined in entry.S */
30 extern const char xen_hypervisor_callback
[];
31 extern const char xen_failsafe_callback
[];
32 extern void xen_sysenter_target(void);
33 extern void xen_syscall_target(void);
34 extern void xen_syscall32_target(void);
36 static unsigned long __init
xen_release_chunk(phys_addr_t start_addr
,
39 struct xen_memory_reservation reservation
= {
44 unsigned long start
, end
;
45 unsigned long len
= 0;
49 start
= PFN_UP(start_addr
);
50 end
= PFN_DOWN(end_addr
);
55 printk(KERN_INFO
"xen_release_chunk: looking at area pfn %lx-%lx: ",
57 for(pfn
= start
; pfn
< end
; pfn
++) {
58 unsigned long mfn
= pfn_to_mfn(pfn
);
60 /* Make sure pfn exists to start with */
61 if (mfn
== INVALID_P2M_ENTRY
|| mfn_to_pfn(mfn
) != pfn
)
64 set_xen_guest_handle(reservation
.extent_start
, &mfn
);
65 reservation
.nr_extents
= 1;
67 ret
= HYPERVISOR_memory_op(XENMEM_decrease_reservation
,
69 WARN(ret
!= 1, "Failed to release memory %lx-%lx err=%d\n",
72 set_phys_to_machine(pfn
, INVALID_P2M_ENTRY
);
76 printk(KERN_CONT
"%ld pages freed\n", len
);
81 static unsigned long __init
xen_return_unused_memory(unsigned long max_pfn
,
82 const struct e820map
*e820
)
84 phys_addr_t max_addr
= PFN_PHYS(max_pfn
);
85 phys_addr_t last_end
= 0;
86 unsigned long released
= 0;
89 for (i
= 0; i
< e820
->nr_map
&& last_end
< max_addr
; i
++) {
90 phys_addr_t end
= e820
->map
[i
].addr
;
91 end
= min(max_addr
, end
);
93 released
+= xen_release_chunk(last_end
, end
);
94 last_end
= e820
->map
[i
].addr
+ e820
->map
[i
].size
;
97 if (last_end
< max_addr
)
98 released
+= xen_release_chunk(last_end
, max_addr
);
100 printk(KERN_INFO
"released %ld pages of unused memory\n", released
);
105 * machine_specific_memory_setup - Hook for machine specific memory setup.
108 char * __init
xen_memory_setup(void)
110 unsigned long max_pfn
= xen_start_info
->nr_pages
;
112 max_pfn
= min(MAX_DOMAIN_PAGES
, max_pfn
);
116 e820_add_region(0, PFN_PHYS((u64
)max_pfn
), E820_RAM
);
119 * Even though this is normal, usable memory under Xen, reserve
120 * ISA memory anyway because too many things think they can poke
123 e820_add_region(ISA_START_ADDRESS
, ISA_END_ADDRESS
- ISA_START_ADDRESS
,
130 * See comment above "struct start_info" in <xen/interface/xen.h>
132 reserve_early(__pa(xen_start_info
->mfn_list
),
133 __pa(xen_start_info
->pt_base
),
136 sanitize_e820_map(e820
.map
, ARRAY_SIZE(e820
.map
), &e820
.nr_map
);
138 xen_return_unused_memory(xen_start_info
->nr_pages
, &e820
);
143 static void xen_idle(void)
150 current_thread_info()->status
&= ~TS_POLLING
;
151 smp_mb__after_clear_bit();
153 current_thread_info()->status
|= TS_POLLING
;
158 * Set the bit indicating "nosegneg" library variants should be used.
159 * We only need to bother in pure 32-bit mode; compat 32-bit processes
160 * can have un-truncated segments, so wrapping around is allowed.
162 static void __init
fiddle_vdso(void)
166 mask
= VDSO32_SYMBOL(&vdso32_int80_start
, NOTE_MASK
);
167 *mask
|= 1 << VDSO_NOTE_NONEGSEG_BIT
;
168 mask
= VDSO32_SYMBOL(&vdso32_sysenter_start
, NOTE_MASK
);
169 *mask
|= 1 << VDSO_NOTE_NONEGSEG_BIT
;
173 static __cpuinit
int register_callback(unsigned type
, const void *func
)
175 struct callback_register callback
= {
177 .address
= XEN_CALLBACK(__KERNEL_CS
, func
),
178 .flags
= CALLBACKF_mask_events
,
181 return HYPERVISOR_callback_op(CALLBACKOP_register
, &callback
);
184 void __cpuinit
xen_enable_sysenter(void)
187 unsigned sysenter_feature
;
190 sysenter_feature
= X86_FEATURE_SEP
;
192 sysenter_feature
= X86_FEATURE_SYSENTER32
;
195 if (!boot_cpu_has(sysenter_feature
))
198 ret
= register_callback(CALLBACKTYPE_sysenter
, xen_sysenter_target
);
200 setup_clear_cpu_cap(sysenter_feature
);
203 void __cpuinit
xen_enable_syscall(void)
208 ret
= register_callback(CALLBACKTYPE_syscall
, xen_syscall_target
);
210 printk(KERN_ERR
"Failed to set syscall callback: %d\n", ret
);
211 /* Pretty fatal; 64-bit userspace has no other
212 mechanism for syscalls. */
215 if (boot_cpu_has(X86_FEATURE_SYSCALL32
)) {
216 ret
= register_callback(CALLBACKTYPE_syscall32
,
217 xen_syscall32_target
);
219 setup_clear_cpu_cap(X86_FEATURE_SYSCALL32
);
221 #endif /* CONFIG_X86_64 */
224 void __init
xen_arch_setup(void)
226 struct physdev_set_iopl set_iopl
;
229 xen_panic_handler_init();
231 HYPERVISOR_vm_assist(VMASST_CMD_enable
, VMASST_TYPE_4gb_segments
);
232 HYPERVISOR_vm_assist(VMASST_CMD_enable
, VMASST_TYPE_writable_pagetables
);
234 if (!xen_feature(XENFEAT_auto_translated_physmap
))
235 HYPERVISOR_vm_assist(VMASST_CMD_enable
,
236 VMASST_TYPE_pae_extended_cr3
);
238 if (register_callback(CALLBACKTYPE_event
, xen_hypervisor_callback
) ||
239 register_callback(CALLBACKTYPE_failsafe
, xen_failsafe_callback
))
242 xen_enable_sysenter();
243 xen_enable_syscall();
246 rc
= HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl
, &set_iopl
);
248 printk(KERN_INFO
"physdev_op failed %d\n", rc
);
251 if (!(xen_start_info
->flags
& SIF_INITDOMAIN
)) {
252 printk(KERN_INFO
"ACPI in unprivileged domain disabled\n");
257 memcpy(boot_command_line
, xen_start_info
->cmd_line
,
258 MAX_GUEST_CMDLINE
> COMMAND_LINE_SIZE
?
259 COMMAND_LINE_SIZE
: MAX_GUEST_CMDLINE
);
263 paravirt_disable_iospace();