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-rw-r--r--lib/libvmmapi/vmmapi.h3
-rw-r--r--lib/libvmmapi/vmmapi_freebsd.c166
2 files changed, 167 insertions, 2 deletions
diff --git a/lib/libvmmapi/vmmapi.h b/lib/libvmmapi/vmmapi.h
index 8428987..4a3db5d 100644
--- a/lib/libvmmapi/vmmapi.h
+++ b/lib/libvmmapi/vmmapi.h
@@ -111,5 +111,8 @@ int vcpu_reset(struct vmctx *ctx, int vcpu);
int vm_setup_freebsd_registers(struct vmctx *ctx, int vcpu,
uint64_t rip, uint64_t cr3, uint64_t gdtbase,
uint64_t rsp);
+int vm_setup_freebsd_registers_i386(struct vmctx *vmctx, int vcpu,
+ uint32_t eip, uint32_t gdtbase,
+ uint32_t esp);
void vm_setup_freebsd_gdt(uint64_t *gdtr);
#endif /* _VMMAPI_H_ */
diff --git a/lib/libvmmapi/vmmapi_freebsd.c b/lib/libvmmapi/vmmapi_freebsd.c
index 9bd2988..d801184 100644
--- a/lib/libvmmapi/vmmapi_freebsd.c
+++ b/lib/libvmmapi/vmmapi_freebsd.c
@@ -35,14 +35,176 @@ __FBSDID("$FreeBSD$");
#include <machine/segments.h>
#include <machine/vmm.h>
+#include <errno.h>
+#include <string.h>
+
#include "vmmapi.h"
+#define I386_TSS_SIZE 104
+
+#define DESC_PRESENT 0x00000080
+#define DESC_LONGMODE 0x00002000
+#define DESC_DEF32 0x00004000
+#define DESC_GRAN 0x00008000
#define DESC_UNUSABLE 0x00010000
#define GUEST_NULL_SEL 0
#define GUEST_CODE_SEL 1
#define GUEST_DATA_SEL 2
-#define GUEST_GDTR_LIMIT (3 * 8 - 1)
+#define GUEST_TSS_SEL 3
+#define GUEST_GDTR_LIMIT64 (3 * 8 - 1)
+
+static struct segment_descriptor i386_gdt[] = {
+ {}, /* NULL */
+ { .sd_lolimit = 0xffff, .sd_type = SDT_MEMER, /* CODE */
+ .sd_p = 1, .sd_hilimit = 0xf, .sd_def32 = 1, .sd_gran = 1 },
+ { .sd_lolimit = 0xffff, .sd_type = SDT_MEMRW, /* DATA */
+ .sd_p = 1, .sd_hilimit = 0xf, .sd_def32 = 1, .sd_gran = 1 },
+ { .sd_lolimit = I386_TSS_SIZE - 1, /* TSS */
+ .sd_type = SDT_SYS386TSS, .sd_p = 1 }
+};
+
+/*
+ * Setup the 'vcpu' register set such that it will begin execution at
+ * 'eip' in flat mode.
+ */
+int
+vm_setup_freebsd_registers_i386(struct vmctx *vmctx, int vcpu, uint32_t eip,
+ uint32_t gdtbase, uint32_t esp)
+{
+ uint64_t cr0, rflags, desc_base;
+ uint32_t desc_access, desc_limit, tssbase;
+ uint16_t gsel;
+ struct segment_descriptor *gdt;
+ int error, tmp;
+
+ /* A 32-bit guest requires unrestricted mode. */
+ error = vm_get_capability(vmctx, vcpu, VM_CAP_UNRESTRICTED_GUEST, &tmp);
+ if (error)
+ goto done;
+ error = vm_set_capability(vmctx, vcpu, VM_CAP_UNRESTRICTED_GUEST, 1);
+ if (error)
+ goto done;
+
+ cr0 = CR0_PE | CR0_NE;
+ if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_CR0, cr0)) != 0)
+ goto done;
+
+ if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_CR4, 0)) != 0)
+ goto done;
+
+ /*
+ * Forcing EFER to 0 causes bhyve to clear the "IA-32e guest
+ * mode" entry control.
+ */
+ if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_EFER, 0)))
+ goto done;
+
+ gdt = vm_map_gpa(vmctx, gdtbase, 0x1000);
+ if (gdt == NULL)
+ return (EFAULT);
+ memcpy(gdt, i386_gdt, sizeof(i386_gdt));
+ desc_base = gdtbase;
+ desc_limit = sizeof(i386_gdt) - 1;
+ error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_GDTR,
+ desc_base, desc_limit, 0);
+ if (error != 0)
+ goto done;
+
+ /* Place the TSS one page above the GDT. */
+ tssbase = gdtbase + 0x1000;
+ gdt[3].sd_lobase = tssbase;
+
+ rflags = 0x2;
+ error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_RFLAGS, rflags);
+ if (error)
+ goto done;
+
+ desc_base = 0;
+ desc_limit = 0xffffffff;
+ desc_access = DESC_GRAN | DESC_DEF32 | DESC_PRESENT | SDT_MEMERA;
+ error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_CS,
+ desc_base, desc_limit, desc_access);
+
+ desc_access = DESC_GRAN | DESC_DEF32 | DESC_PRESENT | SDT_MEMRWA;
+ error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_DS,
+ desc_base, desc_limit, desc_access);
+ if (error)
+ goto done;
+
+ error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_ES,
+ desc_base, desc_limit, desc_access);
+ if (error)
+ goto done;
+
+ error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_FS,
+ desc_base, desc_limit, desc_access);
+ if (error)
+ goto done;
+
+ error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_GS,
+ desc_base, desc_limit, desc_access);
+ if (error)
+ goto done;
+
+ error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_SS,
+ desc_base, desc_limit, desc_access);
+ if (error)
+ goto done;
+
+ desc_base = tssbase;
+ desc_limit = I386_TSS_SIZE - 1;
+ desc_access = DESC_PRESENT | SDT_SYS386BSY;
+ error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_TR,
+ desc_base, desc_limit, desc_access);
+ if (error)
+ goto done;
+
+
+ error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_LDTR, 0, 0,
+ DESC_UNUSABLE);
+ if (error)
+ goto done;
+
+ gsel = GSEL(GUEST_CODE_SEL, SEL_KPL);
+ if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_CS, gsel)) != 0)
+ goto done;
+
+ gsel = GSEL(GUEST_DATA_SEL, SEL_KPL);
+ if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_DS, gsel)) != 0)
+ goto done;
+
+ if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_ES, gsel)) != 0)
+ goto done;
+
+ if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_FS, gsel)) != 0)
+ goto done;
+
+ if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_GS, gsel)) != 0)
+ goto done;
+
+ if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_SS, gsel)) != 0)
+ goto done;
+
+ gsel = GSEL(GUEST_TSS_SEL, SEL_KPL);
+ if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_TR, gsel)) != 0)
+ goto done;
+
+ /* LDTR is pointing to the null selector */
+ if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_LDTR, 0)) != 0)
+ goto done;
+
+ /* entry point */
+ if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_RIP, eip)) != 0)
+ goto done;
+
+ if ((error = vm_set_register(vmctx, vcpu, VM_REG_GUEST_RSP, esp)) != 0)
+ goto done;
+
+ error = 0;
+done:
+ return (error);
+}
void
vm_setup_freebsd_gdt(uint64_t *gdtr)
@@ -168,7 +330,7 @@ vm_setup_freebsd_registers(struct vmctx *vmctx, int vcpu,
goto done;
desc_base = gdtbase;
- desc_limit = GUEST_GDTR_LIMIT;
+ desc_limit = GUEST_GDTR_LIMIT64;
error = vm_set_desc(vmctx, vcpu, VM_REG_GUEST_GDTR,
desc_base, desc_limit, 0);
if (error != 0)
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