Merge remote-tracking branch 'remotes/kraxel/tags/pull-fw_cfg-20151020-1' into staging

fw_cfg: add dma interface, add strings via cmdline.

# gpg: Signature made Tue 20 Oct 2015 07:07:34 BST using RSA key ID D3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>"
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>"
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>"

* remotes/kraxel/tags/pull-fw_cfg-20151020-1:
  fw_cfg: Define a static signature to be returned on DMA port reads
  Enable fw_cfg DMA interface for x86
  Enable fw_cfg DMA interface for ARM
  Implement fw_cfg DMA interface
  fw_cfg DMA interface documentation
  fw_cfg: document fw_cfg_modify_iXX() update functions
  fw_cfg: insert string blobs via qemu cmdline

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 27 insertions, 6 deletions

diff --git a/vl.c b/vl.c
index 7c806a2428..332d8287d8 100644
--- a/vl.c
+++ b/vl.c
@@ -512,6 +512,10 @@ static QemuOptsList qemu_fw_cfg_opts = {
             .type = QEMU_OPT_STRING,
             .help = "Sets the name of the file from which\n"
                     "the fw_cfg blob will be loaded",
+        }, {
+            .name = "string",
+            .type = QEMU_OPT_STRING,
+            .help = "Sets content of the blob to be inserted from a string",
         },
         { /* end of list */ }
     },
@@ -2239,11 +2243,16 @@ char *qemu_find_file(int type, const char *name)
     return NULL;
 }
 
+static inline bool nonempty_str(const char *str)
+{
+    return str && *str;
+}
+
 static int parse_fw_cfg(void *opaque, QemuOpts *opts, Error **errp)
 {
     gchar *buf;
     size_t size;
-    const char *name, *file;
+    const char *name, *file, *str;
 
     if (opaque == NULL) {
         error_report("fw_cfg device not available");
@@ -2251,8 +2260,15 @@ static int parse_fw_cfg(void *opaque, QemuOpts *opts, Error **errp)
     }
     name = qemu_opt_get(opts, "name");
     file = qemu_opt_get(opts, "file");
-    if (name == NULL || *name == '\0' || file == NULL || *file == '\0') {
-        error_report("invalid argument value");
+    str = qemu_opt_get(opts, "string");
+
+    /* we need name and either a file or the content string */
+    if (!(nonempty_str(name) && (nonempty_str(file) || nonempty_str(str)))) {
+        error_report("invalid argument(s)");
+        return -1;
+    }
+    if (nonempty_str(file) && nonempty_str(str)) {
+        error_report("file and string are mutually exclusive");
         return -1;
     }
     if (strlen(name) > FW_CFG_MAX_FILE_PATH - 1) {
@@ -2263,9 +2279,14 @@ static int parse_fw_cfg(void *opaque, QemuOpts *opts, Error **errp)
         error_report("WARNING: externally provided fw_cfg item names "
                      "should be prefixed with \"opt/\"!");
     }
-    if (!g_file_get_contents(file, &buf, &size, NULL)) {
-        error_report("can't load %s", file);
-        return -1;
+    if (nonempty_str(str)) {
+        size = strlen(str); /* NUL terminator NOT included in fw_cfg blob */
+        buf = g_memdup(str, size);
+    } else {
+        if (!g_file_get_contents(file, &buf, &size, NULL)) {
+            error_report("can't load %s", file);
+            return -1;
+        }
     }
     fw_cfg_add_file((FWCfgState *)opaque, name, buf, size);
     return 0;