diff mbox series

[for-7.2,10/21] accel/tcg: Properly implement get_page_addr_code for user-only

Message ID 20220812180806.2128593-11-richard.henderson@linaro.org
State Superseded
Headers show
Series accel/tcg: minimize tlb lookups during translate + user-only PROT_EXEC fixes | expand

Commit Message

Richard Henderson Aug. 12, 2022, 6:07 p.m. UTC 
The current implementation is a no-op, simply returning addr.
This is incorrect, because we ought to be checking the page
permissions for execution.

Make get_page_addr_code inline for both implementations.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 include/exec/exec-all.h | 85 ++++++++++++++---------------------------
 accel/tcg/cputlb.c      |  5 ---
 accel/tcg/user-exec.c   | 15 ++++++++
 3 files changed, 43 insertions(+), 62 deletions(-)
diff mbox series

Patch

diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h
index e7e30d55b8..9f35e3b7a9 100644
--- a/include/exec/exec-all.h
+++ b/include/exec/exec-all.h
@@ -595,43 +595,44 @@  struct MemoryRegionSection *iotlb_to_section(CPUState *cpu,
                                              hwaddr index, MemTxAttrs attrs);
 #endif
 
-#if defined(CONFIG_USER_ONLY)
-void mmap_lock(void);
-void mmap_unlock(void);
-bool have_mmap_lock(void);
-
 /**
- * get_page_addr_code() - user-mode version
+ * get_page_addr_code_hostp()
  * @env: CPUArchState
  * @addr: guest virtual address of guest code
  *
- * Returns @addr.
+ * See get_page_addr_code() (full-system version) for documentation on the
+ * return value.
+ *
+ * Sets *@hostp (when @hostp is non-NULL) as follows.
+ * If the return value is -1, sets *@hostp to NULL. Otherwise, sets *@hostp
+ * to the host address where @addr's content is kept.
+ *
+ * Note: this function can trigger an exception.
+ */
+tb_page_addr_t get_page_addr_code_hostp(CPUArchState *env, target_ulong addr,
+                                        void **hostp);
+
+/**
+ * get_page_addr_code()
+ * @env: CPUArchState
+ * @addr: guest virtual address of guest code
+ *
+ * If we cannot translate and execute from the entire RAM page, or if
+ * the region is not backed by RAM, returns -1. Otherwise, returns the
+ * ram_addr_t corresponding to the guest code at @addr.
+ *
+ * Note: this function can trigger an exception.
  */
 static inline tb_page_addr_t get_page_addr_code(CPUArchState *env,
                                                 target_ulong addr)
 {
-    return addr;
+    return get_page_addr_code_hostp(env, addr, NULL);
 }
 
-/**
- * get_page_addr_code_hostp() - user-mode version
- * @env: CPUArchState
- * @addr: guest virtual address of guest code
- *
- * Returns @addr.
- *
- * If @hostp is non-NULL, sets *@hostp to the host address where @addr's content
- * is kept.
- */
-static inline tb_page_addr_t get_page_addr_code_hostp(CPUArchState *env,
-                                                      target_ulong addr,
-                                                      void **hostp)
-{
-    if (hostp) {
-        *hostp = g2h_untagged(addr);
-    }
-    return addr;
-}
+#if defined(CONFIG_USER_ONLY)
+void mmap_lock(void);
+void mmap_unlock(void);
+bool have_mmap_lock(void);
 
 /**
  * adjust_signal_pc:
@@ -688,36 +689,6 @@  G_NORETURN void cpu_loop_exit_sigbus(CPUState *cpu, target_ulong addr,
 static inline void mmap_lock(void) {}
 static inline void mmap_unlock(void) {}
 
-/**
- * get_page_addr_code() - full-system version
- * @env: CPUArchState
- * @addr: guest virtual address of guest code
- *
- * If we cannot translate and execute from the entire RAM page, or if
- * the region is not backed by RAM, returns -1. Otherwise, returns the
- * ram_addr_t corresponding to the guest code at @addr.
- *
- * Note: this function can trigger an exception.
- */
-tb_page_addr_t get_page_addr_code(CPUArchState *env, target_ulong addr);
-
-/**
- * get_page_addr_code_hostp() - full-system version
- * @env: CPUArchState
- * @addr: guest virtual address of guest code
- *
- * See get_page_addr_code() (full-system version) for documentation on the
- * return value.
- *
- * Sets *@hostp (when @hostp is non-NULL) as follows.
- * If the return value is -1, sets *@hostp to NULL. Otherwise, sets *@hostp
- * to the host address where @addr's content is kept.
- *
- * Note: this function can trigger an exception.
- */
-tb_page_addr_t get_page_addr_code_hostp(CPUArchState *env, target_ulong addr,
-                                        void **hostp);
-
 void tlb_reset_dirty(CPUState *cpu, ram_addr_t start1, ram_addr_t length);
 void tlb_set_dirty(CPUState *cpu, target_ulong vaddr);
 
diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c
index 5db56bcd1e..80a3eb4f1c 100644
--- a/accel/tcg/cputlb.c
+++ b/accel/tcg/cputlb.c
@@ -1532,11 +1532,6 @@  tb_page_addr_t get_page_addr_code_hostp(CPUArchState *env, target_ulong addr,
     return qemu_ram_addr_from_host_nofail(p);
 }
 
-tb_page_addr_t get_page_addr_code(CPUArchState *env, target_ulong addr)
-{
-    return get_page_addr_code_hostp(env, addr, NULL);
-}
-
 static void notdirty_write(CPUState *cpu, vaddr mem_vaddr, unsigned size,
                            CPUIOTLBEntry *iotlbentry, uintptr_t retaddr)
 {
diff --git a/accel/tcg/user-exec.c b/accel/tcg/user-exec.c
index 20ada5472b..a20234fb02 100644
--- a/accel/tcg/user-exec.c
+++ b/accel/tcg/user-exec.c
@@ -199,6 +199,21 @@  void *probe_access(CPUArchState *env, target_ulong addr, int size,
     return size ? g2h(env_cpu(env), addr) : NULL;
 }
 
+tb_page_addr_t get_page_addr_code_hostp(CPUArchState *env, target_ulong addr,
+                                        void **hostp)
+{
+    int flags;
+
+    flags = probe_access_internal(env, addr, 1, MMU_INST_FETCH, true, 0);
+    if (unlikely(flags)) {
+        return -1;
+    }
+    if (hostp) {
+        *hostp = g2h_untagged(addr);
+    }
+    return addr;
+}
+
 /* The softmmu versions of these helpers are in cputlb.c.  */
 
 /*