[Qemu-devel] [PATCH 5/7] kdump: add vmcoreinfo ELF note

["Marc-André Lureau" <marcandre.lureau@redhat.com>]

kdump header provides offset and size of the vmcoreinfo ELF note,
append it if available.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
---
 dump.c | 48 ++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 44 insertions(+), 4 deletions(-)

diff --git a/dump.c b/dump.c
index 8fda5cc1ed..b78bc1fda7 100644
--- a/dump.c
+++ b/dump.c
@@ -788,8 +788,9 @@ static void create_header32(DumpState *s, Error **errp)
     uint32_t sub_hdr_size;
     uint32_t bitmap_blocks;
     uint32_t status = 0;
-    uint64_t offset_note;
+    uint64_t offset_note, offset_vmcoreinfo, size_vmcoreinfo = 0;
     Error *local_err = NULL;
+    uint8_t *vmcoreinfo = NULL;
 
     /* write common header, the version of kdump-compressed format is 6th */
     size = sizeof(DiskDumpHeader32);
@@ -838,7 +839,18 @@ static void create_header32(DumpState *s, Error **errp)
     kh->phys_base = cpu_to_dump32(s, s->dump_info.phys_base);
     kh->dump_level = cpu_to_dump32(s, DUMP_LEVEL);
 
-    offset_note = DISKDUMP_HEADER_BLOCKS * block_size + size;
+    offset_vmcoreinfo = DISKDUMP_HEADER_BLOCKS * block_size + size;
+    if (s->vmcoreinfo) {
+        uint64_t hsize, name_size;
+
+        get_note_sizes(s, s->vmcoreinfo, &hsize, &name_size, &size_vmcoreinfo);
+        vmcoreinfo =
+            s->vmcoreinfo + (DIV_ROUND_UP(hsize, 4) + DIV_ROUND_UP(name_size, 4)) * 4;
+        kh->offset_vmcoreinfo = cpu_to_dump64(s, offset_vmcoreinfo);
+        kh->size_vmcoreinfo = cpu_to_dump32(s, size_vmcoreinfo);
+    }
+
+    offset_note = offset_vmcoreinfo + size_vmcoreinfo;
     kh->offset_note = cpu_to_dump64(s, offset_note);
     kh->note_size = cpu_to_dump32(s, s->note_size);
 
@@ -848,6 +860,14 @@ static void create_header32(DumpState *s, Error **errp)
         goto out;
     }
 
+    if (vmcoreinfo) {
+        if (write_buffer(s->fd, offset_vmcoreinfo, vmcoreinfo,
+                         size_vmcoreinfo) < 0) {
+            error_setg(errp, "dump: failed to vmcoreinfo");
+            goto out;
+        }
+    }
+
     /* write note */
     s->note_buf = g_malloc0(s->note_size);
     s->note_buf_offset = 0;
@@ -888,8 +908,9 @@ static void create_header64(DumpState *s, Error **errp)
     uint32_t sub_hdr_size;
     uint32_t bitmap_blocks;
     uint32_t status = 0;
-    uint64_t offset_note;
+    uint64_t offset_note, offset_vmcoreinfo, size_vmcoreinfo = 0;
     Error *local_err = NULL;
+    uint8_t *vmcoreinfo = NULL;
 
     /* write common header, the version of kdump-compressed format is 6th */
     size = sizeof(DiskDumpHeader64);
@@ -938,7 +959,18 @@ static void create_header64(DumpState *s, Error **errp)
     kh->phys_base = cpu_to_dump64(s, s->dump_info.phys_base);
     kh->dump_level = cpu_to_dump32(s, DUMP_LEVEL);
 
-    offset_note = DISKDUMP_HEADER_BLOCKS * block_size + size;
+    offset_vmcoreinfo = DISKDUMP_HEADER_BLOCKS * block_size + size;
+    if (s->vmcoreinfo) {
+        uint64_t hsize, name_size;
+
+        get_note_sizes(s, s->vmcoreinfo, &hsize, &name_size, &size_vmcoreinfo);
+        vmcoreinfo =
+            s->vmcoreinfo + (DIV_ROUND_UP(hsize, 4) + DIV_ROUND_UP(name_size, 4)) * 4;
+        kh->offset_vmcoreinfo = cpu_to_dump64(s, offset_vmcoreinfo);
+        kh->size_vmcoreinfo = cpu_to_dump64(s, size_vmcoreinfo);
+    }
+
+    offset_note = offset_vmcoreinfo + size_vmcoreinfo;
     kh->offset_note = cpu_to_dump64(s, offset_note);
     kh->note_size = cpu_to_dump64(s, s->note_size);
 
@@ -948,6 +980,14 @@ static void create_header64(DumpState *s, Error **errp)
         goto out;
     }
 
+    if (vmcoreinfo) {
+        if (write_buffer(s->fd, offset_vmcoreinfo, vmcoreinfo,
+                         size_vmcoreinfo) < 0) {
+            error_setg(errp, "dump: failed to vmcoreinfo");
+            goto out;
+        }
+    }
+
     /* write note */
     s->note_buf = g_malloc0(s->note_size);
     s->note_buf_offset = 0;
-- 
2.13.1.395.gf7b71de06