[SeaBIOS] [PATCH v5 4/5] QEMU fw_cfg: Add functions for accessing files by key

[ben at skyportsystems.com]

From: Ben Warren <ben at skyportsystems.com>

When resuming from S3, only fw_cfg file keys are known.

Signed-off-by: Ben Warren <ben at skyportsystems.com>
---
 src/fw/paravirt.c | 23 +++++++++++++++++++++++
 src/fw/paravirt.h |  2 ++
 2 files changed, 25 insertions(+)

diff --git a/src/fw/paravirt.c b/src/fw/paravirt.c
index 4618647..e513dd5 100644
--- a/src/fw/paravirt.c
+++ b/src/fw/paravirt.c
@@ -352,6 +352,17 @@ qemu_cfg_write_file(void *src, struct romfile_s *file, u32 offset, u32 len)
     return len;
 }
 
+// Bare-bones function for writing a file knowing only its unique
+// identifying key (select)
+int
+qemu_cfg_write_file_simple(void *src, u16 key, u32 offset, u32 len)
+{
+    qemu_cfg_select(key);
+    qemu_cfg_skip(offset);
+    qemu_cfg_write(src, len);
+    return len;
+}
+
 static void
 qemu_romfile_add(char *name, int select, int skip, int size)
 {
@@ -370,6 +381,18 @@ qemu_romfile_add(char *name, int select, int skip, int size)
 }
 
 u16
+qemu_get_romfile_key(struct romfile_s *file)
+{
+    struct qemu_romfile_s *qfile;
+    qfile = container_of(file, struct qemu_romfile_s, file);
+    if (!qfile) {
+        warn_internalerror();
+        return 0;
+    }
+    return qfile->select;
+}
+
+u16
 qemu_get_present_cpus_count(void)
 {
     u16 smp_count = 0;
diff --git a/src/fw/paravirt.h b/src/fw/paravirt.h
index fb220d8..16f3d9a 100644
--- a/src/fw/paravirt.h
+++ b/src/fw/paravirt.h
@@ -56,5 +56,7 @@ void qemu_cfg_init(void);
 
 u16 qemu_get_present_cpus_count(void);
 int qemu_cfg_write_file(void *src, struct romfile_s *file, u32 offset, u32 len);
+int qemu_cfg_write_file_simple(void *src, u16 key, u32 offset, u32 len);
+u16 qemu_get_romfile_key(struct romfile_s *file);
 
 #endif
-- 
2.7.4