Re: [Qemu-devel] [PATCH 6/8] ipmi: provide support for FRUs

["Cédric Le Goater" <clg@fr.ibm.com>]

On 02/14/2016 10:25 AM, Marcel Apfelbaum wrote:
> On 02/09/2016 02:13 PM, Cédric Le Goater wrote:
>> This patch provides a simple FRU support for the BMC simulator. FRUs
>> are loaded from a file which name is specified in the object
>> properties, each entry having a fixed size, also specified in the
>> properties. If the file is unknown or not accessible for some reason,
>> a unique entry of 1024 bytes is created as a default. Just enough to
>> start some simulation.
>>
>> Signed-off-by: Cédric Le Goater <clg@fr.ibm.com>
>> ---
>>   hw/ipmi/ipmi_bmc_sim.c | 140 +++++++++++++++++++++++++++++++++++++++++++++++++
>>   1 file changed, 140 insertions(+)
>>
>> diff --git a/hw/ipmi/ipmi_bmc_sim.c b/hw/ipmi/ipmi_bmc_sim.c
>> index 69318eb6b556..b0754893fc08 100644
>> --- a/hw/ipmi/ipmi_bmc_sim.c
>> +++ b/hw/ipmi/ipmi_bmc_sim.c
>> @@ -80,6 +80,9 @@
>>   #define IPMI_CMD_ENTER_SDR_REP_UPD_MODE   0x2A
>>   #define IPMI_CMD_EXIT_SDR_REP_UPD_MODE    0x2B
>>   #define IPMI_CMD_RUN_INIT_AGENT           0x2C
>> +#define IPMI_CMD_GET_FRU_AREA_INFO        0x10
>> +#define IPMI_CMD_READ_FRU_DATA            0x11
>> +#define IPMI_CMD_WRITE_FRU_DATA           0x12
>>   #define IPMI_CMD_GET_SEL_INFO             0x40
>>   #define IPMI_CMD_GET_SEL_ALLOC_INFO       0x41
>>   #define IPMI_CMD_RESERVE_SEL              0x42
>> @@ -122,6 +125,13 @@ typedef struct IPMISdr {
>>       uint8_t overflow;
>>   } IPMISdr;
>>
>> +typedef struct IPMIFru {
>> +    char *filename;
>> +    unsigned int nentries;
>> +    uint16_t size;
>> +    uint8_t *data;
>> +} IPMIFru;
>> +
>>   typedef struct IPMISensor {
>>       uint8_t status;
>>       uint8_t reading;
>> @@ -208,6 +218,7 @@ struct IPMIBmcSim {
>>
>>       IPMISel sel;
>>       IPMISdr sdr;
>> +    IPMIFru fru;
>>       IPMISensor sensors[MAX_SENSORS];
>>       char *sdr_filename;
>>
>> @@ -1314,6 +1325,103 @@ static void get_sel_info(IPMIBmcSim *ibs,
>>       IPMI_ADD_RSP_DATA((ibs->sel.overflow << 7) | 0x02);
>>   }
>>
>> +static void get_fru_area_info(IPMIBmcSim *ibs,
>> +                         uint8_t *cmd, unsigned int cmd_len,
>> +                         uint8_t *rsp, unsigned int *rsp_len,
>> +                         unsigned int max_rsp_len)
>> +{
>> +    uint8_t fruid;
>> +    uint16_t fru_entry_size;
>> +
>> +    IPMI_CHECK_CMD_LEN(3);
> 
> Hi,
> 
> This is little awkward for me. The cmd_len and rsp
> parameters of the macro are implied.

hmm, I am not sure what you mean. Are you concerned by that fact 
we could overflow rsp and cmd ? 

I guess we could probably move the IPMI_CHECK_CMD_LEN in the caller
of these commands and use an array of expected argument lengths.
For rsp, IPMI_ADD_RSP_DATA needs to be used to check that we are not 
exceeding max_rsp_len

> Am I the only one this bothers?
> 
>> +
>> +    fruid = cmd[2];
>> +
>> +    if (fruid >= ibs->fru.nentries) {
>> +        rsp[2] = IPMI_CC_INVALID_DATA_FIELD;
>> +        return;
>> +    }
>> +
>> +    fru_entry_size = ibs->fru.size;
>> +
>> +    IPMI_ADD_RSP_DATA(fru_entry_size & 0xff);
>> +    IPMI_ADD_RSP_DATA(fru_entry_size >> 8 & 0xff);
>> +    IPMI_ADD_RSP_DATA(0x0);
> 
> Same here. By the way, do you have some spec for the above or
> is an ad-hoc encoding of the fields? If yes, you could
> add a reference for the spec.(This is also for the other functions in this patch)

Yes I will add the reference.

Thanks,

C.

 
> Thanks,
> Marcel
> 
>> +}
>> +
>> +#define min(x, y) ((x) < (y) ? (x) : (y))
>> +#define max(x, y) ((x) > (y) ? (x) : (y))
>> +
>> +static void read_fru_data(IPMIBmcSim *ibs,
>> +                         uint8_t *cmd, unsigned int cmd_len,
>> +                         uint8_t *rsp, unsigned int *rsp_len,
>> +                         unsigned int max_rsp_len)
>> +{
>> +    uint8_t fruid;
>> +    uint16_t offset;
>> +    int i;
>> +    uint8_t *fru_entry;
>> +    unsigned int count;
>> +
>> +    IPMI_CHECK_CMD_LEN(5);
>> +
>> +    fruid = cmd[2];
>> +    offset = (cmd[3] | cmd[4] << 8);
>> +
>> +    if (fruid >= ibs->fru.nentries) {
>> +        rsp[2] = IPMI_CC_INVALID_DATA_FIELD;
>> +        return;
>> +    }
>> +
>> +    if (offset >= ibs->fru.size - 1) {
>> +        rsp[2] = IPMI_CC_INVALID_DATA_FIELD;
>> +        return;
>> +    }
>> +
>> +    fru_entry = &ibs->fru.data[fruid * ibs->fru.size];
>> +
>> +    count = min(cmd[5], ibs->fru.size - offset);
>> +
>> +    IPMI_ADD_RSP_DATA(count & 0xff);
>> +    for (i = 0; i < count; i++) {
>> +        IPMI_ADD_RSP_DATA(fru_entry[offset + i]);
>> +    }
>> +}
>> +
>> +static void write_fru_data(IPMIBmcSim *ibs,
>> +                         uint8_t *cmd, unsigned int cmd_len,
>> +                         uint8_t *rsp, unsigned int *rsp_len,
>> +                         unsigned int max_rsp_len)
>> +{
>> +    uint8_t fruid;
>> +    uint16_t offset;
>> +    uint8_t *fru_entry;
>> +    unsigned int count;
>> +
>> +    IPMI_CHECK_CMD_LEN(5);
>> +
>> +    fruid = cmd[2];
>> +    offset = (cmd[3] | cmd[4] << 8);
>> +
>> +    if (fruid >= ibs->fru.nentries) {
>> +        rsp[2] = IPMI_CC_INVALID_DATA_FIELD;
>> +        return;
>> +    }
>> +
>> +    if (offset >= ibs->fru.size - 1) {
>> +        rsp[2] = IPMI_CC_INVALID_DATA_FIELD;
>> +        return;
>> +    }
>> +
>> +    fru_entry = &ibs->fru.data[fruid * ibs->fru.size];
>> +
>> +    count = min(cmd_len - 5, ibs->fru.size - offset);
>> +
>> +    memcpy(fru_entry + offset, cmd + 5, count);
>> +
>> +    IPMI_ADD_RSP_DATA(count & 0xff);
>> +}
>> +
>>   static void reserve_sel(IPMIBmcSim *ibs,
>>                           uint8_t *cmd, unsigned int cmd_len,
>>                           uint8_t *rsp, unsigned int *rsp_len,
>> @@ -1667,6 +1775,9 @@ static const IPMINetfn app_netfn = {
>>   };
>>
>>   static const IPMICmdHandler storage_cmds[] = {
>> +    [IPMI_CMD_GET_FRU_AREA_INFO] = get_fru_area_info,
>> +    [IPMI_CMD_READ_FRU_DATA] = read_fru_data,
>> +    [IPMI_CMD_WRITE_FRU_DATA] = write_fru_data,
>>       [IPMI_CMD_GET_SDR_REP_INFO] = get_sdr_rep_info,
>>       [IPMI_CMD_RESERVE_SDR_REP] = reserve_sdr_rep,
>>       [IPMI_CMD_GET_SDR] = get_sdr,
>> @@ -1766,6 +1877,31 @@ static const VMStateDescription vmstate_ipmi_sim = {
>>       }
>>   };
>>
>> +static void ipmi_fru_init(IPMIFru *fru)
>> +{
>> +    int fsize;
>> +    int size = 0;
>> +
>> +    fsize = get_image_size(fru->filename);
>> +    if (fsize > 0) {
>> +        size = QEMU_ALIGN_UP(fsize, fru->size);
>> +        fru->data = g_malloc0(size);
>> +        if (load_image_size(fru->filename, fru->data, fsize) != fsize) {
>> +            error_report("Could not load file '%s'", fru->filename);
>> +            g_free(fru->data);
>> +            fru->data = NULL;
>> +        }
>> +    }
>> +
>> +    if (!fru->data) {
>> +        /* give one default FRU */
>> +        size = fru->size;
>> +        fru->data = g_malloc0(size);
>> +    }
>> +
>> +    fru->nentries = size / fru->size;
>> +}
>> +
>>   static void ipmi_sim_realize(DeviceState *dev, Error **errp)
> 652776
> 
>>   {
>>       IPMIBmc *b = IPMI_BMC(dev);
>> @@ -1788,6 +1924,8 @@ static void ipmi_sim_realize(DeviceState *dev, Error **errp)
>>
>>       ipmi_sdr_init(ibs);
>>
>> +    ipmi_fru_init(&ibs->fru);
>> +
>>       ibs->acpi_power_state[0] = 0;
>>       ibs->acpi_power_state[1] = 0;
>>
>> @@ -1806,6 +1944,8 @@ static void ipmi_sim_realize(DeviceState *dev, Error **errp)
>>   }
>>
>>   static Property ipmi_sim_properties[] = {
>> +    DEFINE_PROP_UINT16("frusize", IPMIBmcSim, fru.size, 1024),
>> +    DEFINE_PROP_STRING("frufile", IPMIBmcSim, fru.filename),
>>       DEFINE_PROP_STRING("sdr", IPMIBmcSim, sdr_filename),
>>       DEFINE_PROP_END_OF_LIST(),
>>   };
>>
>