[Qemu-devel] [PATCH v4 4/9] dump: Add API to create header of vmcore

[qiaonuohan@cn.fujitsu.com]

From: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>

Functions in this patch are used to gather data of header and sub header in
kdump-compressed format. The following patch will use these functions to gather
data of header, then cache them into struct DumpState.

Signed-off-by: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>
Reviewed-by: Zhang Xiaohe <zhangxh@cn.fujitsu.com>
---
 dump.c                       |  107 ++++++++++++++++++++++++++++++++++++++++++
 include/sysemu/dump_memory.h |   93 ++++++++++++++++++++++++++++++++++++
 2 files changed, 200 insertions(+), 0 deletions(-)

diff --git a/dump.c b/dump.c
index 9ac66be..3b9d4ca 100644
--- a/dump.c
+++ b/dump.c
@@ -681,6 +681,113 @@ static ram_addr_t get_start_block(DumpState *s)
     return -1;
 }
 
+static int create_header32(DumpState *s)
+{
+    struct  disk_dump_header32 *dh;
+    struct  kdump_sub_header32 *kh;
+
+    /* create common header, the version of kdump-compressed format is 5th */
+    dh = g_malloc0(sizeof(struct disk_dump_header32));
+
+    strncpy(dh->signature, KDUMP_SIGNATURE, strlen(KDUMP_SIGNATURE));
+    dh->header_version = 5;
+    dh->block_size = s->page_size;
+    dh->sub_hdr_size = sizeof(struct kdump_sub_header32) + s->note_size;
+    dh->sub_hdr_size = divideup(dh->sub_hdr_size, dh->block_size);
+    dh->max_mapnr = s->max_mapnr;
+    dh->nr_cpus = s->nr_cpus;
+    dh->bitmap_blocks = divideup(s->len_dump_bitmap, s->page_size);
+
+    memcpy(&(dh->utsname.machine), "i686", 4);
+
+    s->dh = dh;
+
+    /* create sub header */
+    kh = g_malloc0(sizeof(struct kdump_sub_header32));
+
+    kh->phys_base = PHYS_BASE;
+    kh->dump_level = DUMP_LEVEL;
+
+    kh->offset_note = DISKDUMP_HEADER_BLOCKS * dh->block_size +
+                        sizeof(struct kdump_sub_header32);
+    kh->note_size = s->note_size;
+
+    s->kh = kh;
+
+    /* get gap between header and sub header */
+    s->offset_sub_header = DISKDUMP_HEADER_BLOCKS * dh->block_size -
+                            sizeof(struct disk_dump_header32);
+
+    /* get gap between header and dump_bitmap */
+    s->offset_dump_bitmap = dh->sub_hdr_size * dh->block_size -
+                            (sizeof(struct kdump_sub_header32) + s->note_size);
+
+    /* get offset of page desc */
+    s->offset_page = (DISKDUMP_HEADER_BLOCKS + dh->sub_hdr_size +
+                        dh->bitmap_blocks) * dh->block_size;
+
+    return 0;
+}
+
+static int create_header64(DumpState *s)
+{
+    struct  disk_dump_header64 *dh;
+    struct  kdump_sub_header64 *kh;
+
+    /* create common header, the version of kdump-compressed format is 5th */
+    dh = g_malloc0(sizeof(struct disk_dump_header64));
+
+    strncpy(dh->signature, KDUMP_SIGNATURE, strlen(KDUMP_SIGNATURE));
+    dh->header_version = 5;
+    dh->block_size = s->page_size;
+    dh->sub_hdr_size = sizeof(struct kdump_sub_header64) + s->note_size;
+    dh->sub_hdr_size = divideup(dh->sub_hdr_size, dh->block_size);
+    dh->max_mapnr = s->max_mapnr;
+    dh->nr_cpus = s->nr_cpus;
+    dh->bitmap_blocks = divideup(s->len_dump_bitmap, s->page_size);
+
+    memcpy(&(dh->utsname.machine), "x86_64", 6);
+
+    s->dh = dh;
+
+    /* create sub header */
+    kh = g_malloc0(sizeof(struct kdump_sub_header64));
+
+    kh->phys_base = PHYS_BASE;
+    kh->dump_level = DUMP_LEVEL;
+
+    kh->offset_note = DISKDUMP_HEADER_BLOCKS * dh->block_size +
+                        sizeof(struct kdump_sub_header64);
+    kh->note_size = s->note_size;
+
+    s->kh = kh;
+
+    /* get gap between header and sub header */
+    s->offset_sub_header = DISKDUMP_HEADER_BLOCKS * dh->block_size -
+                            sizeof(struct disk_dump_header64);
+
+    /* get gap between header and dump_bitmap */
+    s->offset_dump_bitmap = dh->sub_hdr_size * dh->block_size -
+                            (sizeof(struct kdump_sub_header64) + s->note_size);
+
+    /* get offset of page desc */
+    s->offset_page = (DISKDUMP_HEADER_BLOCKS + dh->sub_hdr_size +
+                        dh->bitmap_blocks) * dh->block_size;
+
+    return 0;
+}
+
+/*
+ * gather data of header and sub header
+ */
+static int create_header(DumpState *s)
+{
+    if (s->dump_info.d_machine == EM_386)
+        return create_header32(s);
+    else
+        return create_header64(s);
+}
+
 static int dump_init(DumpState *s, int fd, bool paging, bool has_filter,
                      int64_t begin, int64_t length, Error **errp)
 {
diff --git a/include/sysemu/dump_memory.h b/include/sysemu/dump_memory.h
index ce22c05..56e0f40 100644
--- a/include/sysemu/dump_memory.h
+++ b/include/sysemu/dump_memory.h
@@ -18,6 +18,87 @@
 #include "sysemu/memory_mapping.h"
 #include "sysemu/dump.h"
 
+#define KDUMP_SIGNATURE             "KDUMP   "
+#define SIG_LEN                     (sizeof(KDUMP_SIGNATURE) - 1)
+#define DISKDUMP_HEADER_BLOCKS      (1)
+#define PHYS_BASE                   (0)
+#define DUMP_LEVEL                  (1)
+
+#define divideup(x, y)              (((x) + ((y) - 1)) / (y))
+
+struct new_utsname {
+    char sysname[65];
+    char nodename[65];
+    char release[65];
+    char version[65];
+    char machine[65];
+    char domainname[65];
+};
+
+struct disk_dump_header32 {
+    char signature[SIG_LEN];        /* = "KDUMP   " */
+    int header_version;             /* Dump header version */
+    struct new_utsname utsname;     /* copy of system_utsname */
+    char timestamp[8];              /* Time stamp */
+    unsigned int status;            /* Above flags */
+    int block_size;                 /* Size of a block in byte */
+    int sub_hdr_size;               /* Size of arch dependent header in block */
+    unsigned int bitmap_blocks;     /* Size of Memory bitmap in block */
+    unsigned int max_mapnr;         /* = max_mapnr */
+    unsigned int total_ram_blocks;  /* Number of blocks should be written */
+    unsigned int device_blocks;     /* Number of total blocks in dump device */
+    unsigned int written_blocks;    /* Number of written blocks */
+    unsigned int current_cpu;       /* CPU# which handles dump */
+    int nr_cpus;                    /* Number of CPUs */
+    struct task_struct *tasks[0];
+};
+
+struct disk_dump_header64 {
+    char signature[SIG_LEN];        /* = "KDUMP   " */
+    int header_version;             /* Dump header version */
+    struct new_utsname utsname;     /* copy of system_utsname */
+    char timestamp[20];             /* Time stamp */
+    unsigned int status;            /* Above flags */
+    int block_size;                 /* Size of a block in byte */
+    int sub_hdr_size;               /* Size of arch dependent header in block */
+    unsigned int bitmap_blocks;     /* Size of Memory bitmap in block */
+    unsigned int max_mapnr;         /* = max_mapnr */
+    unsigned int total_ram_blocks;  /* Number of blocks should be written */
+    unsigned int device_blocks;     /* Number of total blocks in dump device */
+    unsigned int written_blocks;    /* Number of written blocks */
+    unsigned int current_cpu;       /* CPU# which handles dump */
+    int nr_cpus;                    /* Number of CPUs */
+    struct task_struct *tasks[0];
+};
+
+struct kdump_sub_header32 {
+    uint32_t phys_base;
+    uint32_t dump_level;            /* header_version 1 and later */
+    uint32_t split;                 /* header_version 2 and later */
+    uint32_t start_pfn;             /* header_version 2 and later */
+    uint32_t end_pfn;               /* header_version 2 and later */
+    uint32_t offset_vmcoreinfo;     /* header_version 3 and later */
+    uint32_t size_vmcoreinfo;       /* header_version 3 and later */
+    uint32_t offset_note;           /* header_version 4 and later */
+    uint32_t note_size;             /* header_version 4 and later */
+    uint32_t offset_eraseinfo;      /* header_version 5 and later */
+    uint32_t size_eraseinfo;        /* header_version 5 and later */
+};
+
+struct kdump_sub_header64 {
+    uint64_t phys_base;
+    uint32_t dump_level;            /* header_version 1 and later */
+    uint32_t split;                 /* header_version 2 and later */
+    uint64_t start_pfn;             /* header_version 2 and later */
+    uint64_t end_pfn;               /* header_version 2 and later */
+    uint64_t offset_vmcoreinfo;     /* header_version 3 and later */
+    uint64_t size_vmcoreinfo;       /* header_version 3 and later */
+    uint64_t offset_note;           /* header_version 4 and later */
+    uint64_t note_size;             /* header_version 4 and later */
+    uint64_t offset_eraseinfo;      /* header_version 5 and later */
+    uint64_t size_eraseinfo;        /* header_version 5 and later */
+};
+
 typedef struct DumpState {
     ArchDumpInfo dump_info;
     MemoryMappingList list;
@@ -35,6 +116,18 @@ typedef struct DumpState {
     int64_t begin;
     int64_t length;
     Error **errp;
+
+    int page_size;
+    unsigned long long max_mapnr;
+    int nr_cpus;
+    void *dh;
+    void *kh;
+    off_t offset_sub_header;
+
+    off_t offset_dump_bitmap;
+    unsigned long len_dump_bitmap;
+
+    off_t offset_page;
 } DumpState;
 
 #endif
-- 
1.7.1