one comment below
On 01/17/14 08:46, qiaonuohan wrote:
DataCache is used to store data temporarily, then the data will be written to
vmcore. These functions will be called later when writing data of page to
vmcore.
Signed-off-by: Qiao Nuohan qiaonuo...@cn.fujitsu.com
Reviewed-by: Laszlo Ersek ler...@redhat.com
---
dump.c| 47 +++
include/sysemu/dump.h |9 +
2 files changed, 56 insertions(+), 0 deletions(-)
diff --git a/dump.c b/dump.c
index 26a1756..fa183cb 100644
--- a/dump.c
+++ b/dump.c
@@ -1173,6 +1173,53 @@ out:
return ret;
}
+static void prepare_data_cache(DataCache *data_cache, DumpState *s,
+ off_t offset)
+{
+data_cache-fd = s-fd;
+data_cache-data_size = 0;
+data_cache-buf_size = BUFSIZE_DATA_CACHE;
+data_cache-buf = g_malloc0(BUFSIZE_DATA_CACHE);
+data_cache-offset = offset;
+}
+
+static int write_cache(DataCache *dc, const void *buf, size_t size,
+ bool flag_sync)
+{
+/*
+ * dc-buf_size should not be less than size, otherwise dc will never be
+ * enough
+ */
+assert(size = dc-buf_size);
+
+/*
+ * if flag_sync is set, synchronize data in dc-buf into vmcore.
+ * otherwise check if the space is enough for caching data in buf, if
not,
+ * write the data in dc-buf to dc-fd and reset dc-buf
+ */
+if ((!flag_sync dc-data_size + size dc-buf_size) ||
+(flag_sync dc-data_size 0)) {
+if (write_buffer(dc-fd, dc-offset, dc-buf, dc-data_size) 0) {
+return -1;
+}
+
+dc-offset += dc-data_size;
+dc-data_size = 0;
+}
+
+if (!flag_sync) {
+memcpy(dc-buf + dc-data_size, buf, size);
+dc-data_size += size;
+}
You don't need to make this block conditional on !flag_sync. By removing
that restriction, the function would become more general.
But I assume you don't need that -- I believe you feed all data to this
function with flag_sync==false, then call it one last time with
(flag_sync==false size==0).
Thanks for adding the assert() and for the type change on buf.
My R-b stands.
Laszlo
+
+return 0;
+}
+
+static void free_data_cache(DataCache *data_cache)
+{
+g_free(data_cache-buf);
+}
+
static ram_addr_t get_start_block(DumpState *s)
{
GuestPhysBlock *block;
diff --git a/include/sysemu/dump.h b/include/sysemu/dump.h
index 6d4d0bc..92a95e4 100644
--- a/include/sysemu/dump.h
+++ b/include/sysemu/dump.h
@@ -41,6 +41,7 @@
#define DISKDUMP_HEADER_BLOCKS (1)
#define BUFSIZE_BITMAP (TARGET_PAGE_SIZE)
#define PFN_BUFBITMAP (CHAR_BIT * BUFSIZE_BITMAP)
+#define BUFSIZE_DATA_CACHE (TARGET_PAGE_SIZE * 4)
typedef struct ArchDumpInfo {
int d_machine; /* Architecture */
@@ -142,6 +143,14 @@ typedef struct QEMU_PACKED KdumpSubHeader64 {
uint64_t max_mapnr_64; /* header_version 6 and later */
} KdumpSubHeader64;
+typedef struct DataCache {
+int fd; /* fd of the file where to write the cached data */
+uint8_t *buf; /* buffer for cached data */
+size_t buf_size;/* size of the buf */
+size_t data_size; /* size of cached data in buf */
+off_t offset; /* offset of the file */
+} DataCache;
+
struct GuestPhysBlockList; /* memory_mapping.h */
int cpu_get_dump_info(ArchDumpInfo *info,
const struct GuestPhysBlockList *guest_phys_blocks);
