[PATCH] i386: PARAVIRT: Use patch site IDs computed from offset in paravirt_ops structure
[linux-2.6] / arch / i386 / kernel / paravirt.c
1 /*  Paravirtualization interfaces
2     Copyright (C) 2006 Rusty Russell IBM Corporation
3
4     This program is free software; you can redistribute it and/or modify
5     it under the terms of the GNU General Public License as published by
6     the Free Software Foundation; either version 2 of the License, or
7     (at your option) any later version.
8
9     This program is distributed in the hope that it will be useful,
10     but WITHOUT ANY WARRANTY; without even the implied warranty of
11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12     GNU General Public License for more details.
13
14     You should have received a copy of the GNU General Public License
15     along with this program; if not, write to the Free Software
16     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17 */
18 #include <linux/errno.h>
19 #include <linux/module.h>
20 #include <linux/efi.h>
21 #include <linux/bcd.h>
22 #include <linux/start_kernel.h>
23
24 #include <asm/bug.h>
25 #include <asm/paravirt.h>
26 #include <asm/desc.h>
27 #include <asm/setup.h>
28 #include <asm/arch_hooks.h>
29 #include <asm/time.h>
30 #include <asm/irq.h>
31 #include <asm/delay.h>
32 #include <asm/fixmap.h>
33 #include <asm/apic.h>
34 #include <asm/tlbflush.h>
35 #include <asm/timer.h>
36
37 /* nop stub */
38 void _paravirt_nop(void)
39 {
40 }
41
42 static void __init default_banner(void)
43 {
44         printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
45                paravirt_ops.name);
46 }
47
48 char *memory_setup(void)
49 {
50         return paravirt_ops.memory_setup();
51 }
52
53 /* Simple instruction patching code. */
54 #define DEF_NATIVE(name, code)                                  \
55         extern const char start_##name[], end_##name[];         \
56         asm("start_" #name ": " code "; end_" #name ":")
57 DEF_NATIVE(cli, "cli");
58 DEF_NATIVE(sti, "sti");
59 DEF_NATIVE(popf, "push %eax; popf");
60 DEF_NATIVE(pushf, "pushf; pop %eax");
61 DEF_NATIVE(iret, "iret");
62 DEF_NATIVE(sti_sysexit, "sti; sysexit");
63
64 static const struct native_insns
65 {
66         const char *start, *end;
67 } native_insns[] = {
68         [PARAVIRT_PATCH(irq_disable)] = { start_cli, end_cli },
69         [PARAVIRT_PATCH(irq_enable)] = { start_sti, end_sti },
70         [PARAVIRT_PATCH(restore_fl)] = { start_popf, end_popf },
71         [PARAVIRT_PATCH(save_fl)] = { start_pushf, end_pushf },
72         [PARAVIRT_PATCH(iret)] = { start_iret, end_iret },
73         [PARAVIRT_PATCH(irq_enable_sysexit)] = { start_sti_sysexit, end_sti_sysexit },
74 };
75
76 static unsigned native_patch(u8 type, u16 clobbers, void *insns, unsigned len)
77 {
78         unsigned int insn_len;
79
80         /* Don't touch it if we don't have a replacement */
81         if (type >= ARRAY_SIZE(native_insns) || !native_insns[type].start)
82                 return len;
83
84         insn_len = native_insns[type].end - native_insns[type].start;
85
86         /* Similarly if we can't fit replacement. */
87         if (len < insn_len)
88                 return len;
89
90         memcpy(insns, native_insns[type].start, insn_len);
91         return insn_len;
92 }
93
94 void init_IRQ(void)
95 {
96         paravirt_ops.init_IRQ();
97 }
98
99 static void native_flush_tlb(void)
100 {
101         __native_flush_tlb();
102 }
103
104 /*
105  * Global pages have to be flushed a bit differently. Not a real
106  * performance problem because this does not happen often.
107  */
108 static void native_flush_tlb_global(void)
109 {
110         __native_flush_tlb_global();
111 }
112
113 static void native_flush_tlb_single(u32 addr)
114 {
115         __native_flush_tlb_single(addr);
116 }
117
118 /* These are in entry.S */
119 extern void native_iret(void);
120 extern void native_irq_enable_sysexit(void);
121
122 static int __init print_banner(void)
123 {
124         paravirt_ops.banner();
125         return 0;
126 }
127 core_initcall(print_banner);
128
129 struct paravirt_ops paravirt_ops = {
130         .name = "bare hardware",
131         .paravirt_enabled = 0,
132         .kernel_rpl = 0,
133         .shared_kernel_pmd = 1, /* Only used when CONFIG_X86_PAE is set */
134
135         .patch = native_patch,
136         .banner = default_banner,
137         .arch_setup = paravirt_nop,
138         .memory_setup = machine_specific_memory_setup,
139         .get_wallclock = native_get_wallclock,
140         .set_wallclock = native_set_wallclock,
141         .time_init = hpet_time_init,
142         .init_IRQ = native_init_IRQ,
143
144         .cpuid = native_cpuid,
145         .get_debugreg = native_get_debugreg,
146         .set_debugreg = native_set_debugreg,
147         .clts = native_clts,
148         .read_cr0 = native_read_cr0,
149         .write_cr0 = native_write_cr0,
150         .read_cr2 = native_read_cr2,
151         .write_cr2 = native_write_cr2,
152         .read_cr3 = native_read_cr3,
153         .write_cr3 = native_write_cr3,
154         .read_cr4 = native_read_cr4,
155         .read_cr4_safe = native_read_cr4_safe,
156         .write_cr4 = native_write_cr4,
157         .save_fl = native_save_fl,
158         .restore_fl = native_restore_fl,
159         .irq_disable = native_irq_disable,
160         .irq_enable = native_irq_enable,
161         .safe_halt = native_safe_halt,
162         .halt = native_halt,
163         .wbinvd = native_wbinvd,
164         .read_msr = native_read_msr_safe,
165         .write_msr = native_write_msr_safe,
166         .read_tsc = native_read_tsc,
167         .read_pmc = native_read_pmc,
168         .get_scheduled_cycles = native_read_tsc,
169         .get_cpu_khz = native_calculate_cpu_khz,
170         .load_tr_desc = native_load_tr_desc,
171         .set_ldt = native_set_ldt,
172         .load_gdt = native_load_gdt,
173         .load_idt = native_load_idt,
174         .store_gdt = native_store_gdt,
175         .store_idt = native_store_idt,
176         .store_tr = native_store_tr,
177         .load_tls = native_load_tls,
178         .write_ldt_entry = write_dt_entry,
179         .write_gdt_entry = write_dt_entry,
180         .write_idt_entry = write_dt_entry,
181         .load_esp0 = native_load_esp0,
182
183         .set_iopl_mask = native_set_iopl_mask,
184         .io_delay = native_io_delay,
185
186 #ifdef CONFIG_X86_LOCAL_APIC
187         .apic_write = native_apic_write,
188         .apic_write_atomic = native_apic_write_atomic,
189         .apic_read = native_apic_read,
190         .setup_boot_clock = setup_boot_APIC_clock,
191         .setup_secondary_clock = setup_secondary_APIC_clock,
192 #endif
193         .set_lazy_mode = paravirt_nop,
194
195         .pagetable_setup_start = native_pagetable_setup_start,
196         .pagetable_setup_done = native_pagetable_setup_done,
197
198         .flush_tlb_user = native_flush_tlb,
199         .flush_tlb_kernel = native_flush_tlb_global,
200         .flush_tlb_single = native_flush_tlb_single,
201
202         .map_pt_hook = paravirt_nop,
203
204         .alloc_pt = paravirt_nop,
205         .alloc_pd = paravirt_nop,
206         .alloc_pd_clone = paravirt_nop,
207         .release_pt = paravirt_nop,
208         .release_pd = paravirt_nop,
209
210         .set_pte = native_set_pte,
211         .set_pte_at = native_set_pte_at,
212         .set_pmd = native_set_pmd,
213         .pte_update = paravirt_nop,
214         .pte_update_defer = paravirt_nop,
215
216         .ptep_get_and_clear = native_ptep_get_and_clear,
217
218 #ifdef CONFIG_X86_PAE
219         .set_pte_atomic = native_set_pte_atomic,
220         .set_pte_present = native_set_pte_present,
221         .set_pud = native_set_pud,
222         .pte_clear = native_pte_clear,
223         .pmd_clear = native_pmd_clear,
224
225         .pmd_val = native_pmd_val,
226         .make_pmd = native_make_pmd,
227 #endif
228
229         .pte_val = native_pte_val,
230         .pgd_val = native_pgd_val,
231
232         .make_pte = native_make_pte,
233         .make_pgd = native_make_pgd,
234
235         .irq_enable_sysexit = native_irq_enable_sysexit,
236         .iret = native_iret,
237
238         .dup_mmap = paravirt_nop,
239         .exit_mmap = paravirt_nop,
240         .activate_mm = paravirt_nop,
241
242         .startup_ipi_hook = paravirt_nop,
243 };
244
245 /*
246  * NOTE: CONFIG_PARAVIRT is experimental and the paravirt_ops
247  * semantics are subject to change. Hence we only do this
248  * internal-only export of this, until it gets sorted out and
249  * all lowlevel CPU ops used by modules are separately exported.
250  */
251 EXPORT_SYMBOL_GPL(paravirt_ops);