apb: QOMify IOMMU

[qemu.git] / util / osdep.c

diff --git a/util/osdep.c b/util/osdep.c
index 06fb1cfda6ed38ff11820dea7c167ca0ed3177d6..1231f9f8768cc817ef3bee406ef25b0f517ba23e 100644 (file)
--- a/util/osdep.c
+++ b/util/osdep.c
@@ -73,7 +73,52 @@ int qemu_madvise(void *addr, size_t len, int advice)
 #endif
 }
 
+static int qemu_mprotect__osdep(void *addr, size_t size, int prot)
+{
+    g_assert(!((uintptr_t)addr & ~qemu_real_host_page_mask));
+    g_assert(!(size & ~qemu_real_host_page_mask));
+
+#ifdef _WIN32
+    DWORD old_protect;
+
+    if (!VirtualProtect(addr, size, prot, &old_protect)) {
+        error_report("%s: VirtualProtect failed with error code %ld",
+                     __func__, GetLastError());
+        return -1;
+    }
+    return 0;
+#else
+    if (mprotect(addr, size, prot)) {
+        error_report("%s: mprotect failed: %s", __func__, strerror(errno));
+        return -1;
+    }
+    return 0;
+#endif
+}
+
+int qemu_mprotect_rwx(void *addr, size_t size)
+{
+#ifdef _WIN32
+    return qemu_mprotect__osdep(addr, size, PAGE_EXECUTE_READWRITE);
+#else
+    return qemu_mprotect__osdep(addr, size, PROT_READ | PROT_WRITE | PROT_EXEC);
+#endif
+}
+
+int qemu_mprotect_none(void *addr, size_t size)
+{
+#ifdef _WIN32
+    return qemu_mprotect__osdep(addr, size, PAGE_NOACCESS);
+#else
+    return qemu_mprotect__osdep(addr, size, PROT_NONE);
+#endif
+}
+
 #ifndef _WIN32
+
+static int fcntl_op_setlk = -1;
+static int fcntl_op_getlk = -1;
+
 /*
  * Dups an fd and sets the flags
  */
@@ -140,6 +185,96 @@ static int qemu_parse_fdset(const char *param)
 {
     return qemu_parse_fd(param);
 }
+
+static void qemu_probe_lock_ops(void)
+{
+    if (fcntl_op_setlk == -1) {
+#ifdef F_OFD_SETLK
+        int fd;
+        int ret;
+        struct flock fl = {
+            .l_whence = SEEK_SET,
+            .l_start  = 0,
+            .l_len    = 0,
+            .l_type   = F_WRLCK,
+        };
+
+        fd = open("/dev/null", O_RDWR);
+        if (fd < 0) {
+            fprintf(stderr,
+                    "Failed to open /dev/null for OFD lock probing: %s\n",
+                    strerror(errno));
+            fcntl_op_setlk = F_SETLK;
+            fcntl_op_getlk = F_GETLK;
+            return;
+        }
+        ret = fcntl(fd, F_OFD_GETLK, &fl);
+        close(fd);
+        if (!ret) {
+            fcntl_op_setlk = F_OFD_SETLK;
+            fcntl_op_getlk = F_OFD_GETLK;
+        } else {
+            fcntl_op_setlk = F_SETLK;
+            fcntl_op_getlk = F_GETLK;
+        }
+#else
+        fcntl_op_setlk = F_SETLK;
+        fcntl_op_getlk = F_GETLK;
+#endif
+    }
+}
+
+bool qemu_has_ofd_lock(void)
+{
+    qemu_probe_lock_ops();
+#ifdef F_OFD_SETLK
+    return fcntl_op_setlk == F_OFD_SETLK;
+#else
+    return false;
+#endif
+}
+
+static int qemu_lock_fcntl(int fd, int64_t start, int64_t len, int fl_type)
+{
+    int ret;
+    struct flock fl = {
+        .l_whence = SEEK_SET,
+        .l_start  = start,
+        .l_len    = len,
+        .l_type   = fl_type,
+    };
+    qemu_probe_lock_ops();
+    ret = fcntl(fd, fcntl_op_setlk, &fl);
+    return ret == -1 ? -errno : 0;
+}
+
+int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive)
+{
+    return qemu_lock_fcntl(fd, start, len, exclusive ? F_WRLCK : F_RDLCK);
+}
+
+int qemu_unlock_fd(int fd, int64_t start, int64_t len)
+{
+    return qemu_lock_fcntl(fd, start, len, F_UNLCK);
+}
+
+int qemu_lock_fd_test(int fd, int64_t start, int64_t len, bool exclusive)
+{
+    int ret;
+    struct flock fl = {
+        .l_whence = SEEK_SET,
+        .l_start  = start,
+        .l_len    = len,
+        .l_type   = exclusive ? F_WRLCK : F_RDLCK,
+    };
+    qemu_probe_lock_ops();
+    ret = fcntl(fd, fcntl_op_getlk, &fl);
+    if (ret == -1) {
+        return -errno;
+    } else {
+        return fl.l_type == F_UNLCK ? 0 : -EAGAIN;
+    }
+}
 #endif
 
 /*