[PATCH v2 resend 3/3] makedumpfile: implementation of dealing with kdump-compressed dumpfile with ENOSPC error

[Wang, Xiao/Wang Xiao]

kdump-compressed:
Dump the bitmap before any page header and page data. This format use
"status" of "disk_dump_header" to indicate that it has been modified.

Signed-of-by: Wang Xiao <wangx.fnst at cn.fujitsu.com>
---
  diskdump_mod.h |    2 +
  makedumpfile.c |   85 
++++++++++++++++++++++++++++++++++++++++++++++++++++---
  2 files changed, 82 insertions(+), 5 deletions(-)

diff --git a/diskdump_mod.h b/diskdump_mod.h
index dd24eb2..a0d3439 100644
--- a/diskdump_mod.h
+++ b/diskdump_mod.h
@@ -96,6 +96,8 @@ struct kdump_sub_header {
  #define DUMP_DH_COMPRESSED_SNAPPY    0x4
                      /* paged is compressed with snappy */

+#define DUMP_DH_COMPRESSED_INCOMPLETE    0x8 /* this is an incomplete 
dumpfile*/
+
  /* descriptor of each page for vmcore */
  typedef struct page_desc {
      off_t            offset;        /* the offset of the page data*/
diff --git a/makedumpfile.c b/makedumpfile.c
index 13f0f35..84b26bb 100644
--- a/makedumpfile.c
+++ b/makedumpfile.c
@@ -3771,6 +3771,71 @@ out_close_file:
  }

  int
+check_and_modify_kdump_headers(char *filename) {
+    int fd, ret = FALSE;
+    struct disk_dump_header dh;
+
+    if (!read_disk_dump_header(&dh, filename))
+        return FALSE;
+
+    if ((fd = open(filename, O_RDWR)) < 0) {
+        ERRMSG("Can't open the dump file(%s). %s\n",
+                filename, strerror(errno));
+        return FALSE;
+    }
+
+    /*
+     * Set the incomplete flag to the status of disk_dump_header.
+     */
+    dh.status |= DUMP_DH_COMPRESSED_INCOMPLETE;
+
+    /*
+     * It's safe to overwrite the disk_dump_header.
+     */
+    if (!write_buffer(fd, 0, &dh, sizeof(struct disk_dump_header), 
filename))
+        goto out_close_file;
+
+    ret = TRUE;
+out_close_file:
+    if (close(fd) < 0) {
+        ERRMSG("Can't close the dump file(%s). %s\n",
+                filename, strerror(errno));
+    }
+
+    return ret;
+}
+
+int
+check_and_modify_multiple_kdump_headers() {
+    int i, status, ret = TRUE;
+    pid_t pid;
+    pid_t array_pid[info->num_dumpfile];
+
+    for (i = 0; i < info->num_dumpfile; i++) {
+        if ((pid = fork()) < 0) {
+            return FALSE;
+
+        } else if (pid == 0) { /* Child */
+            if (!check_and_modify_kdump_headers(SPLITTING_DUMPFILE(i)))
+                exit(1);
+            exit(0);
+        }
+        array_pid[i] = pid;
+    }
+
+    for (i = 0; i < info->num_dumpfile; i++) {
+        waitpid(array_pid[i], &status, WUNTRACED);
+        if (!WIFEXITED(status) || WEXITSTATUS(status) == 1) {
+            ERRMSG("Check and modify the incomplete dumpfile(%s) 
failed.\n",
+                   SPLITTING_DUMPFILE(i));
+            ret = FALSE;
+        }
+    }
+
+    return ret;
+}
+
+int
  write_cache_bufsz(struct cache_data *cd)
  {
      if (!cd->buf_size)
@@ -7113,11 +7178,11 @@ write_kdump_pages_and_bitmap_cyclic(struct 
cache_data *cd_header, struct cache_d
          if (!exclude_unnecessary_pages_cyclic(&cycle))
              return FALSE;

-        if (!write_kdump_pages_cyclic(cd_header, cd_page, &pd_zero,
-                    &offset_data, &cycle))
+        if (!write_kdump_bitmap2_cyclic(&cycle))
              return FALSE;

-        if (!write_kdump_bitmap2_cyclic(&cycle))
+        if (!write_kdump_pages_cyclic(cd_header, cd_page, &pd_zero,
+                    &offset_data, &cycle))
              return FALSE;
      }

@@ -8080,12 +8145,12 @@ writeout_dumpfile(void)
      } else {
          if (!write_kdump_header())
              goto out;
+        if (!write_kdump_bitmap())
+            goto out;
          if (!write_kdump_pages(&cd_header, &cd_page))
              goto out;
          if (!write_kdump_eraseinfo(&cd_page))
              goto out;
-        if (!write_kdump_bitmap())
-            goto out;
      }
      if (info->flag_flatten) {
          if (!write_end_flat_header())
@@ -8296,6 +8361,16 @@ retry:
                      if (check_and_modify_elf_headers(info->name_dumpfile))
                          MSG("This is an incomplete dumpfile,"
                              " but might analyzable.\n");
+                } else {
+                    if (info->flag_split) {
+                        if (check_and_modify_multiple_kdump_headers())
+                            MSG("The splited dumpfiles are incomplete,"
+                                " but might analyzable.\n");
+                    } else {
+                        if 
(check_and_modify_kdump_headers(info->name_dumpfile))
+                            MSG("This is an incomplete dumpfile,"
+                                " but might analyzable.\n");
+                    }
                  }
              }

-- 
1.7.1