KVM: x86: Consolidate flags for __linearize()

Consolidate @write and @fetch of __linearize() into a set of flags so that
additional flags can be added without needing more/new boolean parameters,
to precisely identify the access type.

No functional change intended.

Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com>
Reviewed-by: Chao Gao <chao.gao@intel.com>
Acked-by: Kai Huang <kai.huang@intel.com>
Tested-by: Xuelian Guo <xuelian.guo@intel.com>
Link: https://lore.kernel.org/r/20230913124227.12574-2-binbin.wu@linux.intel.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 2673cd5c46cb486b9e78a20c589462552f0b4747..87ee1802166a2c069b9d2af4577d73a8a97063ca 100644 (file)
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -687,8 +687,8 @@ static unsigned insn_alignment(struct x86_emulate_ctxt *ctxt, unsigned size)
 static __always_inline int __linearize(struct x86_emulate_ctxt *ctxt,
                                       struct segmented_address addr,
                                       unsigned *max_size, unsigned size,
-                                      bool write, bool fetch,
-                                      enum x86emul_mode mode, ulong *linear)
+                                      enum x86emul_mode mode, ulong *linear,
+                                      unsigned int flags)
 {
        struct desc_struct desc;
        bool usable;
@@ -717,11 +717,11 @@ static __always_inline int __linearize(struct x86_emulate_ctxt *ctxt,
                if (!usable)
                        goto bad;
                /* code segment in protected mode or read-only data segment */
-               if ((((ctxt->mode != X86EMUL_MODE_REAL) && (desc.type & 8))
-                                       || !(desc.type & 2)) && write)
+               if ((((ctxt->mode != X86EMUL_MODE_REAL) && (desc.type & 8)) || !(desc.type & 2)) &&
+                   (flags & X86EMUL_F_WRITE))
                        goto bad;
                /* unreadable code segment */
-               if (!fetch && (desc.type & 8) && !(desc.type & 2))
+               if (!(flags & X86EMUL_F_FETCH) && (desc.type & 8) && !(desc.type & 2))
                        goto bad;
                lim = desc_limit_scaled(&desc);
                if (!(desc.type & 8) && (desc.type & 4)) {
@@ -757,8 +757,8 @@ static int linearize(struct x86_emulate_ctxt *ctxt,
                     ulong *linear)
 {
        unsigned max_size;
-       return __linearize(ctxt, addr, &max_size, size, write, false,
-                          ctxt->mode, linear);
+       return __linearize(ctxt, addr, &max_size, size, ctxt->mode, linear,
+                          write ? X86EMUL_F_WRITE : 0);
 }
 
 static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst)
@@ -771,7 +771,8 @@ static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst)
 
        if (ctxt->op_bytes != sizeof(unsigned long))
                addr.ea = dst & ((1UL << (ctxt->op_bytes << 3)) - 1);
-       rc = __linearize(ctxt, addr, &max_size, 1, false, true, ctxt->mode, &linear);
+       rc = __linearize(ctxt, addr, &max_size, 1, ctxt->mode, &linear,
+                        X86EMUL_F_FETCH);
        if (rc == X86EMUL_CONTINUE)
                ctxt->_eip = addr.ea;
        return rc;
@@ -907,8 +908,8 @@ static int __do_insn_fetch_bytes(struct x86_emulate_ctxt *ctxt, int op_size)
         * boundary check itself.  Instead, we use max_size to check
         * against op_size.
         */
-       rc = __linearize(ctxt, addr, &max_size, 0, false, true, ctxt->mode,
-                        &linear);
+       rc = __linearize(ctxt, addr, &max_size, 0, ctxt->mode, &linear,
+                        X86EMUL_F_FETCH);
        if (unlikely(rc != X86EMUL_CONTINUE))
                return rc;
 

diff --git a/arch/x86/kvm/kvm_emulate.h b/arch/x86/kvm/kvm_emulate.h
index be7aeb9b8ea3b152b269870e5a737642a492e192..e24c8ac7b9304c2ab5d4cfea99a680bf33979454 100644 (file)
--- a/arch/x86/kvm/kvm_emulate.h
+++ b/arch/x86/kvm/kvm_emulate.h
@@ -88,6 +88,10 @@ struct x86_instruction_info {
 #define X86EMUL_IO_NEEDED       5 /* IO is needed to complete emulation */
 #define X86EMUL_INTERCEPTED     6 /* Intercepted by nested VMCB/VMCS */
 
+/* x86-specific emulation flags */
+#define X86EMUL_F_WRITE                        BIT(0)
+#define X86EMUL_F_FETCH                        BIT(1)
+
 struct x86_emulate_ops {
        void (*vm_bugged)(struct x86_emulate_ctxt *ctxt);
        /*