On 02/20/17 21:14, ben@skyportsystems.com wrote:
From: Ben Warren ben@skyportsystems.com
Due to memory contraints, when resuming from S3 the fw_cfg "files" API
isn't available. This adds a simple API to get a file 'key', and to
write to the file using the key as a reference.
src/fw/paravirt.c | 32 ++++++++++++++++++++++++++------
src/fw/paravirt.h | 2 ++
2 files changed, 28 insertions(+), 6 deletions(-)
diff --git a/src/fw/paravirt.c b/src/fw/paravirt.c
index 4618647..225b08b 100644
--- a/src/fw/paravirt.c
+++ b/src/fw/paravirt.c
@@ -329,6 +329,17 @@ qemu_cfg_read_file(struct romfile_s *file, void *dst, u32 maxlen)
return file->size;
}
+// 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;
+}
int
qemu_cfg_write_file(void *src, struct romfile_s *file, u32 offset, u32 len)
{
@@ -339,15 +350,12 @@ qemu_cfg_write_file(void *src, struct romfile_s *file, u32 offset, u32 len)
warn_internalerror();
return -1;
}
- struct qemu_romfile_s *qfile;
- qfile = container_of(file, struct qemu_romfile_s, file);
- u16 key = qemu_get_romfile_key(file);
if (offset == 0) {
/* Do it in one transfer */
}
One of the ideas that I mentioned here was to move not just the second
branch of the "if" to qemu_cfg_write_file_simple(), but the entire "if"
-- both branches. Because, qemu_cfg_write_entry() looks suitable for S3
too, and if that kind of optimization makes sense for normal boot, then
it makes sense for S3 resume as well.
Anyway, this is not a functional problem, I won't obsess about it.
Reviewed-by: Laszlo Ersek lersek@redhat.com
Thanks
Laszlo
@@ -370,6 +378,18 @@ 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;
- if (file->copy != qemu_cfg_read_file) {
warn_internalerror();
return 0;
- }
- qfile = container_of(file, struct qemu_romfile_s, file);
- 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