Re: [RFC v4 4/9] file-posix: introduce get_sysfs_str_val for device zoned model.

[Damien Le Moal <damien.lemoal@opensource.wdc.com>]

On 7/12/22 15:17, Hannes Reinecke wrote:
> On 7/12/22 04:13, Sam Li wrote:
>> Signed-off-by: Sam Li <faithilikerun@gmail.com>
>> ---
>>   block/file-posix.c           | 60 ++++++++++++++++++++++++++++++++++++
>>   include/block/block-common.h |  4 +--
>>   2 files changed, 62 insertions(+), 2 deletions(-)
>>
>> diff --git a/block/file-posix.c b/block/file-posix.c
>> index 3161d39ea4..42708012ff 100644
>> --- a/block/file-posix.c
>> +++ b/block/file-posix.c
>> @@ -1279,6 +1279,65 @@ out:
>>   #endif
>>   }
>>   
>> +/*
>> + * Convert the zoned attribute file in sysfs to internal value.
>> + */
>> +static zone_model get_sysfs_str_val(int fd, struct stat *st) {
>> +#ifdef CONFIG_LINUX
>> +    char buf[32];
>> +    char *sysfspath = NULL;
>> +    int ret, offset;
>> +    int sysfd = -1;
>> +
>> +    if (S_ISCHR(st->st_mode)) {
>> +        if (ioctl(fd, SG_GET_SG_TABLESIZE, &ret) == 0) {
>> +            return ret;
>> +        }
>> +        return -ENOTSUP;
>> +    }
>> +
>> +    if (!S_ISBLK(st->st_mode)) {
>> +        return -ENOTSUP;
>> +    }
>> +
>> +    sysfspath = g_strdup_printf("/sys/dev/block/%u:%u/queue/zoned",
>> +                                major(st->st_rdev), minor(st->st_rdev));
>> +    sysfd = open(sysfspath, O_RDONLY);
>> +    if (sysfd == -1) {
>> +        ret = -errno;
>> +        goto out;
>> +    }
>> +    offset = 0;
>> +    do {
>> +        ret = read(sysfd, buf + offset, sizeof(buf) - 1 + offset);
>> +        if (ret > 0) {
>> +            offset += ret;
>> +        }
>> +    } while (ret == -1);
>> +    /* The file is ended with '\n' */
>> +    if (buf[ret - 1] == '\n') {
>> +        buf[ret - 1] = '\0';
>> +    }
>> +
>> +    if (strcmp(buf, "host-managed") == 0) {
>> +        return BLK_Z_HM;
>> +    } else if (strcmp(buf, "host-aware") == 0) {
>> +        return BLK_Z_HA;
>> +    } else {
>> +        return -ENOTSUP;
>> +    }
>> +
>> +out:
>> +    if (sysfd != -1) {
>> +        close(sysfd);
>> +    }
>> +    g_free(sysfspath);
>> +    return ret;
>> +#else
>> +    return -ENOTSUP;
>> +#endif
>> +}
>> +
>>   static int hdev_get_max_segments(int fd, struct stat *st) {
>>       return get_sysfs_long_val(fd, st, "max_segments");
>>   }
>> @@ -1885,6 +1944,7 @@ static int handle_aiocb_zone_mgmt(void *opaque) {
>>       int64_t len = aiocb->aio_nbytes;
>>       zone_op op = aiocb->zone_mgmt.op;
>>   
>> +    zone_model mod;
>>       struct blk_zone_range range;
>>       const char *ioctl_name;
>>       unsigned long ioctl_op;
>> diff --git a/include/block/block-common.h b/include/block/block-common.h
>> index 78cddeeda5..35e00afe8e 100644
>> --- a/include/block/block-common.h
>> +++ b/include/block/block-common.h
>> @@ -56,8 +56,8 @@ typedef enum zone_op {
>>   } zone_op;
>>   
>>   typedef enum zone_model {
>> -    BLK_Z_HM,
>> -    BLK_Z_HA,
>> +    BLK_Z_HM = 0x1,
>> +    BLK_Z_HA = 0x2,
>>   } zone_model;
>>   
>>   typedef enum BlkZoneCondition {
> 
> This hunk is unrelated, please move it into a different patch.

This actually belong to patch 1 where this enum is introduced. No need for
a different patch.

> 
> Cheers,
> 
> Hannes


-- 
Damien Le Moal
Western Digital Research