paravirt: refactor struct paravirt_ops into smaller pv_*_ops
This patch refactors the paravirt_ops structure into groups of
functionally related ops:
pv_info - random info, rather than function entrypoints
pv_init_ops - functions used at boot time (some for module_init too)
pv_misc_ops - lazy mode, which didn't fit well anywhere else
pv_time_ops - time-related functions
pv_cpu_ops - various privileged instruction ops
pv_irq_ops - operations for managing interrupt state
pv_apic_ops - APIC operations
pv_mmu_ops - operations for managing pagetables
There are several motivations for this:
1. Some of these ops will be general to all x86, and some will be
i386/x86-64 specific. This makes it easier to share common stuff
while allowing separate implementations where needed.
2. At the moment we must export all of paravirt_ops, but modules only
need selected parts of it. This allows us to export on a case by case
basis (and also choose which export license we want to apply).
3. Functional groupings make things a bit more readable.
Struct paravirt_ops is now only used as a template to generate
patch-site identifiers, and to extract function pointers for inserting
into jmp/calls when patching. It is only instantiated when needed.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Cc: Zach Amsden <zach@vmware.com>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Anthony Liguory <aliguori@us.ibm.com>
Cc: "Glauber de Oliveira Costa" <glommer@gmail.com>
Cc: Jun Nakajima <jun.nakajima@intel.com>
diff --git a/drivers/lguest/lguest.c b/drivers/lguest/lguest.c
index ee1c6d0..ca9b844 100644
--- a/drivers/lguest/lguest.c
+++ b/drivers/lguest/lguest.c
@@ -23,7 +23,7 @@
*
* So how does the kernel know it's a Guest? The Guest starts at a special
* entry point marked with a magic string, which sets up a few things then
- * calls here. We replace the native functions in "struct paravirt_ops"
+ * calls here. We replace the native functions various "paravirt" structures
* with our Guest versions, then boot like normal. :*/
/*
@@ -331,7 +331,7 @@
}
/*G:038 That's enough excitement for now, back to ploughing through each of
- * the paravirt_ops (we're about 1/3 of the way through).
+ * the different pv_ops structures (we're about 1/3 of the way through).
*
* This is the Local Descriptor Table, another weird Intel thingy. Linux only
* uses this for some strange applications like Wine. We don't do anything
@@ -558,7 +558,7 @@
lazy_hcall(LHCALL_FLUSH_TLB, 1, 0, 0);
}
-/* Unfortunately for Lguest, the paravirt_ops for page tables were based on
+/* Unfortunately for Lguest, the pv_mmu_ops for page tables were based on
* native page table operations. On native hardware you can set a new page
* table entry whenever you want, but if you want to remove one you have to do
* a TLB flush (a TLB is a little cache of page table entries kept by the CPU).
@@ -782,7 +782,7 @@
clocksource_register(&lguest_clock);
/* Now we've set up our clock, we can use it as the scheduler clock */
- paravirt_ops.sched_clock = lguest_sched_clock;
+ pv_time_ops.sched_clock = lguest_sched_clock;
/* We can't set cpumask in the initializer: damn C limitations! Set it
* here and register our timer device. */
@@ -902,7 +902,7 @@
/*G:050
* Patching (Powerfully Placating Performance Pedants)
*
- * We have already seen that "struct paravirt_ops" lets us replace simple
+ * We have already seen that pv_ops structures let us replace simple
* native instructions with calls to the appropriate back end all throughout
* the kernel. This allows the same kernel to run as a Guest and as a native
* kernel, but it's slow because of all the indirect branches.
@@ -927,10 +927,10 @@
{
const char *start, *end;
} lguest_insns[] = {
- [PARAVIRT_PATCH(irq_disable)] = { lgstart_cli, lgend_cli },
- [PARAVIRT_PATCH(irq_enable)] = { lgstart_sti, lgend_sti },
- [PARAVIRT_PATCH(restore_fl)] = { lgstart_popf, lgend_popf },
- [PARAVIRT_PATCH(save_fl)] = { lgstart_pushf, lgend_pushf },
+ [PARAVIRT_PATCH(pv_irq_ops.irq_disable)] = { lgstart_cli, lgend_cli },
+ [PARAVIRT_PATCH(pv_irq_ops.irq_enable)] = { lgstart_sti, lgend_sti },
+ [PARAVIRT_PATCH(pv_irq_ops.restore_fl)] = { lgstart_popf, lgend_popf },
+ [PARAVIRT_PATCH(pv_irq_ops.save_fl)] = { lgstart_pushf, lgend_pushf },
};
/* Now our patch routine is fairly simple (based on the native one in
@@ -957,9 +957,9 @@
return insn_len;
}
-/*G:030 Once we get to lguest_init(), we know we're a Guest. The paravirt_ops
- * structure in the kernel provides a single point for (almost) every routine
- * we have to override to avoid privileged instructions. */
+/*G:030 Once we get to lguest_init(), we know we're a Guest. The pv_ops
+ * structures in the kernel provide points for (almost) every routine we have
+ * to override to avoid privileged instructions. */
__init void lguest_init(void *boot)
{
/* Copy boot parameters first: the Launcher put the physical location
@@ -974,54 +974,68 @@
/* We're under lguest, paravirt is enabled, and we're running at
* privilege level 1, not 0 as normal. */
- paravirt_ops.name = "lguest";
- paravirt_ops.paravirt_enabled = 1;
- paravirt_ops.kernel_rpl = 1;
+ pv_info.name = "lguest";
+ pv_info.paravirt_enabled = 1;
+ pv_info.kernel_rpl = 1;
/* We set up all the lguest overrides for sensitive operations. These
* are detailed with the operations themselves. */
- paravirt_ops.save_fl = save_fl;
- paravirt_ops.restore_fl = restore_fl;
- paravirt_ops.irq_disable = irq_disable;
- paravirt_ops.irq_enable = irq_enable;
- paravirt_ops.load_gdt = lguest_load_gdt;
- paravirt_ops.memory_setup = lguest_memory_setup;
- paravirt_ops.cpuid = lguest_cpuid;
- paravirt_ops.write_cr3 = lguest_write_cr3;
- paravirt_ops.flush_tlb_user = lguest_flush_tlb_user;
- paravirt_ops.flush_tlb_single = lguest_flush_tlb_single;
- paravirt_ops.flush_tlb_kernel = lguest_flush_tlb_kernel;
- paravirt_ops.set_pte = lguest_set_pte;
- paravirt_ops.set_pte_at = lguest_set_pte_at;
- paravirt_ops.set_pmd = lguest_set_pmd;
+
+ /* interrupt-related operations */
+ pv_irq_ops.init_IRQ = lguest_init_IRQ;
+ pv_irq_ops.save_fl = save_fl;
+ pv_irq_ops.restore_fl = restore_fl;
+ pv_irq_ops.irq_disable = irq_disable;
+ pv_irq_ops.irq_enable = irq_enable;
+ pv_irq_ops.safe_halt = lguest_safe_halt;
+
+ /* init-time operations */
+ pv_init_ops.memory_setup = lguest_memory_setup;
+ pv_init_ops.patch = lguest_patch;
+
+ /* Intercepts of various cpu instructions */
+ pv_cpu_ops.load_gdt = lguest_load_gdt;
+ pv_cpu_ops.cpuid = lguest_cpuid;
+ pv_cpu_ops.load_idt = lguest_load_idt;
+ pv_cpu_ops.iret = lguest_iret;
+ pv_cpu_ops.load_esp0 = lguest_load_esp0;
+ pv_cpu_ops.load_tr_desc = lguest_load_tr_desc;
+ pv_cpu_ops.set_ldt = lguest_set_ldt;
+ pv_cpu_ops.load_tls = lguest_load_tls;
+ pv_cpu_ops.set_debugreg = lguest_set_debugreg;
+ pv_cpu_ops.clts = lguest_clts;
+ pv_cpu_ops.read_cr0 = lguest_read_cr0;
+ pv_cpu_ops.write_cr0 = lguest_write_cr0;
+ pv_cpu_ops.read_cr4 = lguest_read_cr4;
+ pv_cpu_ops.write_cr4 = lguest_write_cr4;
+ pv_cpu_ops.write_gdt_entry = lguest_write_gdt_entry;
+ pv_cpu_ops.write_idt_entry = lguest_write_idt_entry;
+ pv_cpu_ops.wbinvd = lguest_wbinvd;
+
+ /* pagetable management */
+ pv_mmu_ops.write_cr3 = lguest_write_cr3;
+ pv_mmu_ops.flush_tlb_user = lguest_flush_tlb_user;
+ pv_mmu_ops.flush_tlb_single = lguest_flush_tlb_single;
+ pv_mmu_ops.flush_tlb_kernel = lguest_flush_tlb_kernel;
+ pv_mmu_ops.set_pte = lguest_set_pte;
+ pv_mmu_ops.set_pte_at = lguest_set_pte_at;
+ pv_mmu_ops.set_pmd = lguest_set_pmd;
+ pv_mmu_ops.read_cr2 = lguest_read_cr2;
+ pv_mmu_ops.read_cr3 = lguest_read_cr3;
+
#ifdef CONFIG_X86_LOCAL_APIC
- paravirt_ops.apic_write = lguest_apic_write;
- paravirt_ops.apic_write_atomic = lguest_apic_write;
- paravirt_ops.apic_read = lguest_apic_read;
+ /* apic read/write intercepts */
+ pv_apic_ops.apic_write = lguest_apic_write;
+ pv_apic_ops.apic_write_atomic = lguest_apic_write;
+ pv_apic_ops.apic_read = lguest_apic_read;
#endif
- paravirt_ops.load_idt = lguest_load_idt;
- paravirt_ops.iret = lguest_iret;
- paravirt_ops.load_esp0 = lguest_load_esp0;
- paravirt_ops.load_tr_desc = lguest_load_tr_desc;
- paravirt_ops.set_ldt = lguest_set_ldt;
- paravirt_ops.load_tls = lguest_load_tls;
- paravirt_ops.set_debugreg = lguest_set_debugreg;
- paravirt_ops.clts = lguest_clts;
- paravirt_ops.read_cr0 = lguest_read_cr0;
- paravirt_ops.write_cr0 = lguest_write_cr0;
- paravirt_ops.init_IRQ = lguest_init_IRQ;
- paravirt_ops.read_cr2 = lguest_read_cr2;
- paravirt_ops.read_cr3 = lguest_read_cr3;
- paravirt_ops.read_cr4 = lguest_read_cr4;
- paravirt_ops.write_cr4 = lguest_write_cr4;
- paravirt_ops.write_gdt_entry = lguest_write_gdt_entry;
- paravirt_ops.write_idt_entry = lguest_write_idt_entry;
- paravirt_ops.patch = lguest_patch;
- paravirt_ops.safe_halt = lguest_safe_halt;
- paravirt_ops.get_wallclock = lguest_get_wallclock;
- paravirt_ops.time_init = lguest_time_init;
- paravirt_ops.set_lazy_mode = lguest_lazy_mode;
- paravirt_ops.wbinvd = lguest_wbinvd;
+
+ /* time operations */
+ pv_time_ops.get_wallclock = lguest_get_wallclock;
+ pv_time_ops.time_init = lguest_time_init;
+
+ pv_misc_ops.set_lazy_mode = lguest_lazy_mode;
+
/* Now is a good time to look at the implementations of these functions
* before returning to the rest of lguest_init(). */