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

[Corey Minyard <cminyard@mvista.com>]

On 02/15/2016 12:40 PM, Marcel Apfelbaum wrote:
> On 02/15/2016 07:17 PM, Cédric Le Goater wrote:
>> 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 ?
>
> Not really, no. Something more simple:
>
> IPMI_CHECK_CMD_LEN(3) should be actually IPMI_CHECK_CMD_LEN(3, 
> cmd_len, rsp).
> What bothers me is that both cmd_len and rsp are implied by the macro.

I would tend to agree.  The hidden stuff in these macros was really a 
bad idea in
hindsight.

-corey

>
> In other words, we don't know what parameters IPMI_CHECK_CMD_LEN 
> really has.
> "3" is for sure not enough, so we need to guess or look a the macro 
> definition
> to see what it uses.
>
> But again, maybe is only me.
>
> Thanks,
> Marcel
>
>
>>
>> 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)
>>>
>>>
>>>>    {
>>>>        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(),
>>>>    };
>>>>
>>>
>>
>