In the next patch we'd like to reuse the image decompression facility
without installing the output as a ROM at a specific guest-phys address.
In addition, expose LOAD_IMAGE_MAX_GUNZIP_BYTES, because that's a
straightforward "max_sz" argument for the new load_image_gzipped_buffer().
Signed-off-by: Laszlo Ersek <ler...@redhat.com>
---
Notes:
v3:
- unchanged
include/hw/loader.h | 9 +++++++++
hw/core/loader.c | 30 +++++++++++++++++++++---------
2 files changed, 30 insertions(+), 9 deletions(-)
diff --git a/include/hw/loader.h b/include/hw/loader.h
index 6481639..8997620 100644
--- a/include/hw/loader.h
+++ b/include/hw/loader.h
@@ -15,8 +15,17 @@ int get_image_size(const char *filename);
int load_image(const char *filename, uint8_t *addr); /* deprecated */
ssize_t load_image_size(const char *filename, void *addr, size_t size);
int load_image_targphys(const char *filename, hwaddr,
uint64_t max_sz);
+
+/* This is the limit on the maximum uncompressed image size that
+ * load_image_gzipped_buffer() and load_image_gzipped() will read. It prevents
+ * g_malloc() in those functions from allocating a huge amount of memory.
+ */
+#define LOAD_IMAGE_MAX_GUNZIP_BYTES (256 << 20)
+
+int load_image_gzipped_buffer(const char *filename, uint64_t max_sz,
+ uint8_t **buffer);
int load_image_gzipped(const char *filename, hwaddr addr, uint64_t max_sz);
#define ELF_LOAD_FAILED -1
#define ELF_LOAD_NOT_ELF -2
diff --git a/hw/core/loader.c b/hw/core/loader.c
index 7527fd3..933ab64 100644
--- a/hw/core/loader.c
+++ b/hw/core/loader.c
@@ -613,16 +613,11 @@ int load_ramdisk(const char *filename, hwaddr addr,
uint64_t max_sz)
return load_uboot_image(filename, NULL, &addr, NULL, IH_TYPE_RAMDISK,
NULL, NULL);
}
-/* This simply prevents g_malloc in the function below from allocating
- * a huge amount of memory, by placing a limit on the maximum
- * uncompressed image size that load_image_gzipped will read.
- */
-#define LOAD_IMAGE_MAX_GUNZIP_BYTES (256 << 20)
-
-/* Load a gzip-compressed kernel. */
-int load_image_gzipped(const char *filename, hwaddr addr, uint64_t max_sz)
+/* Load a gzip-compressed kernel to a dynamically allocated buffer. */
+int load_image_gzipped_buffer(const char *filename, uint64_t max_sz,
+ uint8_t **buffer)
{
uint8_t *compressed_data = NULL;
uint8_t *data = NULL;
gsize len;
@@ -652,17 +647,34 @@ int load_image_gzipped(const char *filename, hwaddr addr,
uint64_t max_sz)
filename);
goto out;
}
- rom_add_blob_fixed(filename, data, bytes, addr);
+ /* trim to actual size and return to caller */
+ *buffer = g_realloc(data, bytes);
ret = bytes;
+ /* ownership has been transferred to caller */
+ data = NULL;
out:
g_free(compressed_data);
g_free(data);
return ret;
}
+/* Load a gzip-compressed kernel. */
+int load_image_gzipped(const char *filename, hwaddr addr, uint64_t max_sz)
+{
+ int bytes;
+ uint8_t *data;
+
+ bytes = load_image_gzipped_buffer (filename, max_sz, &data);
+ if (bytes != -1) {
+ rom_add_blob_fixed(filename, data, bytes, addr);
+ g_free(data);
+ }
+ return bytes;
+}
+
/*
* Functions for reboot-persistent memory regions.
* - used for vga bios and option roms.
* - also linux kernel (-kernel / -initrd).
--
1.8.3.1
