KVM: x86: introduce linear_{read,write}_system

Wrap the common invocation of ctxt->ops->read_std and ctxt->ops->write_std, so
as to have a smaller patch when the functions grow another argument.

Fixes: 129a72a0d3c8 ("KVM: x86: Introduce segmented_write_std", 2017-01-12)
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 143b7ae526240395e557da13a7ba6235c6e4ad2b..fcf54642b29379bfc08f64898e81a24e40027f45 100644 (file)
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -812,6 +812,19 @@ static inline int jmp_rel(struct x86_emulate_ctxt *ctxt, int rel)
        return assign_eip_near(ctxt, ctxt->_eip + rel);
 }
 
+static int linear_read_system(struct x86_emulate_ctxt *ctxt, ulong linear,
+                             void *data, unsigned size)
+{
+       return ctxt->ops->read_std(ctxt, linear, data, size, &ctxt->exception);
+}
+
+static int linear_write_system(struct x86_emulate_ctxt *ctxt,
+                              ulong linear, void *data,
+                              unsigned int size)
+{
+       return ctxt->ops->write_std(ctxt, linear, data, size, &ctxt->exception);
+}
+
 static int segmented_read_std(struct x86_emulate_ctxt *ctxt,
                              struct segmented_address addr,
                              void *data,
@@ -1496,8 +1509,7 @@ static int read_interrupt_descriptor(struct x86_emulate_ctxt *ctxt,
                return emulate_gp(ctxt, index << 3 | 0x2);
 
        addr = dt.address + index * 8;
-       return ctxt->ops->read_std(ctxt, addr, desc, sizeof *desc,
-                                  &ctxt->exception);
+       return linear_read_system(ctxt, addr, desc, sizeof *desc);
 }
 
 static void get_descriptor_table_ptr(struct x86_emulate_ctxt *ctxt,
@@ -1560,8 +1572,7 @@ static int read_segment_descriptor(struct x86_emulate_ctxt *ctxt,
        if (rc != X86EMUL_CONTINUE)
                return rc;
 
-       return ctxt->ops->read_std(ctxt, *desc_addr_p, desc, sizeof(*desc),
-                                  &ctxt->exception);
+       return linear_read_system(ctxt, *desc_addr_p, desc, sizeof(*desc));
 }
 
 /* allowed just for 8 bytes segments */
@@ -1575,8 +1586,7 @@ static int write_segment_descriptor(struct x86_emulate_ctxt *ctxt,
        if (rc != X86EMUL_CONTINUE)
                return rc;
 
-       return ctxt->ops->write_std(ctxt, addr, desc, sizeof *desc,
-                                   &ctxt->exception);
+       return linear_write_system(ctxt, addr, desc, sizeof *desc);
 }
 
 static int __load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
@@ -1737,8 +1747,7 @@ static int __load_segment_descriptor(struct x86_emulate_ctxt *ctxt,
                                return ret;
                }
        } else if (ctxt->mode == X86EMUL_MODE_PROT64) {
-               ret = ctxt->ops->read_std(ctxt, desc_addr+8, &base3,
-                               sizeof(base3), &ctxt->exception);
+               ret = linear_read_system(ctxt, desc_addr+8, &base3, sizeof(base3));
                if (ret != X86EMUL_CONTINUE)
                        return ret;
                if (emul_is_noncanonical_address(get_desc_base(&seg_desc) |
@@ -2051,11 +2060,11 @@ static int __emulate_int_real(struct x86_emulate_ctxt *ctxt, int irq)
        eip_addr = dt.address + (irq << 2);
        cs_addr = dt.address + (irq << 2) + 2;
 
-       rc = ops->read_std(ctxt, cs_addr, &cs, 2, &ctxt->exception);
+       rc = linear_read_system(ctxt, cs_addr, &cs, 2);
        if (rc != X86EMUL_CONTINUE)
                return rc;
 
-       rc = ops->read_std(ctxt, eip_addr, &eip, 2, &ctxt->exception);
+       rc = linear_read_system(ctxt, eip_addr, &eip, 2);
        if (rc != X86EMUL_CONTINUE)
                return rc;
 
@@ -3053,35 +3062,30 @@ static int task_switch_16(struct x86_emulate_ctxt *ctxt,
                          u16 tss_selector, u16 old_tss_sel,
                          ulong old_tss_base, struct desc_struct *new_desc)
 {
-       const struct x86_emulate_ops *ops = ctxt->ops;
        struct tss_segment_16 tss_seg;
        int ret;
        u32 new_tss_base = get_desc_base(new_desc);
 
-       ret = ops->read_std(ctxt, old_tss_base, &tss_seg, sizeof tss_seg,
-                           &ctxt->exception);
+       ret = linear_read_system(ctxt, old_tss_base, &tss_seg, sizeof tss_seg);
        if (ret != X86EMUL_CONTINUE)
                return ret;
 
        save_state_to_tss16(ctxt, &tss_seg);
 
-       ret = ops->write_std(ctxt, old_tss_base, &tss_seg, sizeof tss_seg,
-                            &ctxt->exception);
+       ret = linear_write_system(ctxt, old_tss_base, &tss_seg, sizeof tss_seg);
        if (ret != X86EMUL_CONTINUE)
                return ret;
 
-       ret = ops->read_std(ctxt, new_tss_base, &tss_seg, sizeof tss_seg,
-                           &ctxt->exception);
+       ret = linear_read_system(ctxt, new_tss_base, &tss_seg, sizeof tss_seg);
        if (ret != X86EMUL_CONTINUE)
                return ret;
 
        if (old_tss_sel != 0xffff) {
                tss_seg.prev_task_link = old_tss_sel;
 
-               ret = ops->write_std(ctxt, new_tss_base,
-                                    &tss_seg.prev_task_link,
-                                    sizeof tss_seg.prev_task_link,
-                                    &ctxt->exception);
+               ret = linear_write_system(ctxt, new_tss_base,
+                                         &tss_seg.prev_task_link,
+                                         sizeof tss_seg.prev_task_link);
                if (ret != X86EMUL_CONTINUE)
                        return ret;
        }
@@ -3197,38 +3201,34 @@ static int task_switch_32(struct x86_emulate_ctxt *ctxt,
                          u16 tss_selector, u16 old_tss_sel,
                          ulong old_tss_base, struct desc_struct *new_desc)
 {
-       const struct x86_emulate_ops *ops = ctxt->ops;
        struct tss_segment_32 tss_seg;
        int ret;
        u32 new_tss_base = get_desc_base(new_desc);
        u32 eip_offset = offsetof(struct tss_segment_32, eip);
        u32 ldt_sel_offset = offsetof(struct tss_segment_32, ldt_selector);
 
-       ret = ops->read_std(ctxt, old_tss_base, &tss_seg, sizeof tss_seg,
-                           &ctxt->exception);
+       ret = linear_read_system(ctxt, old_tss_base, &tss_seg, sizeof tss_seg);
        if (ret != X86EMUL_CONTINUE)
                return ret;
 
        save_state_to_tss32(ctxt, &tss_seg);
 
        /* Only GP registers and segment selectors are saved */
-       ret = ops->write_std(ctxt, old_tss_base + eip_offset, &tss_seg.eip,
-                            ldt_sel_offset - eip_offset, &ctxt->exception);
+       ret = linear_write_system(ctxt, old_tss_base + eip_offset, &tss_seg.eip,
+                                 ldt_sel_offset - eip_offset);
        if (ret != X86EMUL_CONTINUE)
                return ret;
 
-       ret = ops->read_std(ctxt, new_tss_base, &tss_seg, sizeof tss_seg,
-                           &ctxt->exception);
+       ret = linear_read_system(ctxt, new_tss_base, &tss_seg, sizeof tss_seg);
        if (ret != X86EMUL_CONTINUE)
                return ret;
 
        if (old_tss_sel != 0xffff) {
                tss_seg.prev_task_link = old_tss_sel;
 
-               ret = ops->write_std(ctxt, new_tss_base,
-                                    &tss_seg.prev_task_link,
-                                    sizeof tss_seg.prev_task_link,
-                                    &ctxt->exception);
+               ret = linear_write_system(ctxt, new_tss_base,
+                                         &tss_seg.prev_task_link,
+                                         sizeof tss_seg.prev_task_link);
                if (ret != X86EMUL_CONTINUE)
                        return ret;
        }