Re: [Qemu-devel] [PATCH] HMP: support specifying dump format for dump-guest-memory

[Christian Borntraeger <borntraeger@de.ibm.com>]

On 01/04/14 15:25, Christian Borntraeger wrote:
> On 01/04/14 10:33, Qiao Nuohan wrote:
>> Dumping guest memory is available to specify the dump format now. This patch
>> adds options '-z|-l|-s' to HMP command dump-guest-memory to specify dumping in
>> kdump-compression format, with zlib/lzo/snappy compression. And without these
>> options ELF format will be used.
>>
>> The discussion about this feature is here:
>>
>> http://lists.nongnu.org/archive/html/qemu-devel/2014-03/msg04235.html
>>
>> Signed-off-by: Qiao Nuohan <qiaonuohan@cn.fujitsu.com>
>> Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com>
> 
> Looks good. I was able to take a zlib dump on s390. 


In other words: 
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>

> 
> 
>> ---
>>  hmp-commands.hx | 11 +++++++----
>>  hmp.c           | 25 ++++++++++++++++++++++++-
>>  2 files changed, 31 insertions(+), 5 deletions(-)
>>
>> diff --git a/hmp-commands.hx b/hmp-commands.hx
>> index f3fc514..4b9989f 100644
>> --- a/hmp-commands.hx
>> +++ b/hmp-commands.hx
>> @@ -998,8 +998,8 @@ ETEXI
>>
>>      {
>>          .name       = "dump-guest-memory",
>> -        .args_type  = "paging:-p,filename:F,begin:i?,length:i?",
>> -        .params     = "[-p] filename [begin] [length]",
>> +        .args_type  = "paging:-p,zlib:-z,lzo:-l,snappy:-s,filename:F,begin:i?,length:i?",
>> +        .params     = "[-p] [-z|-l|-s] filename [begin] [length]",
>>          .help       = "dump guest memory to file"
>>                        "\n\t\t\t begin(optional): the starting physical address"
>>                        "\n\t\t\t length(optional): the memory size, in bytes",
>> @@ -1008,12 +1008,15 @@ ETEXI
>>
>>
>>  STEXI
>> -@item dump-guest-memory [-p] @var{protocol} @var{begin} @var{length}
>> +@item dump-guest-memory [-p] [-z|-l|-s] @var{protocol} @var{begin} @var{length}
>>  @findex dump-guest-memory
>>  Dump guest memory to @var{protocol}. The file can be processed with crash or
>> -gdb.
>> +gdb. Without -z|-l|-s, the dump format is ELF.
>>    filename: dump file name
>>      paging: do paging to get guest's memory mapping
>> +      zlib: dump in kdump-compressed format, with zlib compression
>> +       lzo: dump in kdump-compressed format, with lzo compression
>> +    snappy: dump in kdump-compressed format, with snappy compression
>>       begin: the starting physical address. It's optional, and should be
>>              specified with length together.
>>      length: the memory size, in bytes. It's optional, and should be specified
>> diff --git a/hmp.c b/hmp.c
>> index 2f279c4..37c3961 100644
>> --- a/hmp.c
>> +++ b/hmp.c
>> @@ -1308,16 +1308,39 @@ void hmp_dump_guest_memory(Monitor *mon, const QDict *qdict)
>>  {
>>      Error *errp = NULL;
>>      int paging = qdict_get_try_bool(qdict, "paging", 0);
>> +    int zlib = qdict_get_try_bool(qdict, "zlib", 0);
>> +    int lzo = qdict_get_try_bool(qdict, "lzo", 0);
>> +    int snappy = qdict_get_try_bool(qdict, "snappy", 0);
>>      const char *file = qdict_get_str(qdict, "filename");
>>      bool has_begin = qdict_haskey(qdict, "begin");
>>      bool has_length = qdict_haskey(qdict, "length");
>> -    /* kdump-compressed format is not supported for HMP */
>>      bool has_format = false;
>>      int64_t begin = 0;
>>      int64_t length = 0;
>>      enum DumpGuestMemoryFormat dump_format = DUMP_GUEST_MEMORY_FORMAT_ELF;
>>      char *prot;
>>
>> +    if ((zlib + lzo + snappy) > 1) {
>> +        error_setg(&errp, "only one of '-z|-l|-s' can be set");
>> +        hmp_handle_error(mon, &errp);
>> +        return;
>> +    }
>> +
>> +    if (zlib) {
>> +        has_format = true;
>> +        dump_format = DUMP_GUEST_MEMORY_FORMAT_KDUMP_ZLIB;
>> +    }
>> +
>> +    if (lzo) {
>> +        has_format = true;
>> +        dump_format = DUMP_GUEST_MEMORY_FORMAT_KDUMP_LZO;
>> +    }
>> +
>> +    if (snappy) {
>> +        has_format = true;
>> +        dump_format = DUMP_GUEST_MEMORY_FORMAT_KDUMP_SNAPPY;
>> +    }
>> +
>>      if (has_begin) {
>>          begin = qdict_get_int(qdict, "begin");
>>      }
>>
> 
>