Re: [PATCH 3/3] lightnvm: export per lun information to user

From: Wenwei Tao
Date: Tue Mar 22 2016 - 07:28:34 EST

I notice that sysfs already have lun information exposed, we only need
to add some more,

2016-03-21 18:27 GMT+08:00 Matias BjÃrling <mb@xxxxxxxxxxx>:
> On 03/19/2016 05:58 PM, Wenwei Tao wrote:
>>
>> Export per lun information to user, let the user
>> know more detail information about underlying device.
>>
>> Signed-off-by: Wenwei Tao <ww.tao0320@xxxxxxxxx>
>> ---
>> drivers/lightnvm/core.c | 59
>> ++++++++++++++++++++++++++++++++++++++++++-
>> drivers/lightnvm/gennvm.c | 34 +++++++++++++++++++++++++
>> include/linux/lightnvm.h | 3 +++
>> include/uapi/linux/lightnvm.h | 23 +++++++++++++++++
>> 4 files changed, 118 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
>> index 84bc72d..7701eab 100644
>> --- a/drivers/lightnvm/core.c
>> +++ b/drivers/lightnvm/core.c
>> @@ -28,7 +28,6 @@
>> #include <linux/miscdevice.h>
>> #include <linux/lightnvm.h>
>> #include <linux/sched/sysctl.h>
>> -#include <uapi/linux/lightnvm.h>
>>
>> static LIST_HEAD(nvm_targets);
>> static LIST_HEAD(nvm_mgrs);
>> @@ -1041,6 +1040,62 @@ static long nvm_ioctl_dev_remove(struct file *file,
>> void __user *arg)
>> return __nvm_configure_remove(&remove);
>> }
>>
>> +static long nvm_ioctl_dev_luns_status(struct file *file, void __user
>> *arg)
>> +{
>> + struct nvm_dev *dev;
>> + struct nvm_ioctl_luns_status *status;
>> + long ret = -EINVAL;
>> +
>> + if (!capable(CAP_SYS_ADMIN))
>> + return -EPERM;
>> +
>> + status = kzalloc(sizeof(struct nvm_ioctl_luns_status),
>> GFP_KERNEL);
>> + if (!status)
>> + return -ENOMEM;
>> +
>> + if (copy_from_user(status, arg,
>> + sizeof(struct nvm_ioctl_luns_status))) {
>> + ret = -EFAULT;
>> + goto out;
>> + }
>> +
>> + status->dev[DISK_NAME_LEN - 1] = '\0';
>> + down_write(&nvm_lock);
>> + dev = nvm_find_nvm_dev(status->dev);
>> + up_write(&nvm_lock);
>> + if (!dev) {
>> + pr_err("nvm: device not found\n");
>> + goto out;
>> + }
>> +
>> + if (!dev->mt) {
>> + pr_info("nvm: device has no media manager registered.\n");
>> + ret = -ENODEV;
>> + goto out;
>> + }
>> +
>> + if (status->lun_begin > status->lun_end ||
>> + status->lun_end > dev->nr_luns) {
>> + pr_err("nvm: lun out of bound (%u:%u > %u)\n",
>> + status->lun_begin, status->lun_end, dev->nr_luns);
>> + goto out;
>> + }
>> +
>> + dev->mt->get_luns_status(dev, status);
>> +
>> + if (copy_to_user(arg, status,
>> + sizeof(struct nvm_ioctl_luns_status))) {
>> + ret = -EFAULT;
>> + goto out;
>> + }
>> +
>> + ret = 0;
>> +
>> +out:
>> + kfree(status);
>> + return ret;
>> +}
>> +
>> static void nvm_setup_nvm_sb_info(struct nvm_sb_info *info)
>> {
>> info->seqnr = 1;
>> @@ -1150,6 +1205,8 @@ static long nvm_ctl_ioctl(struct file *file, uint
>> cmd, unsigned long arg)
>> return nvm_ioctl_dev_create(file, argp);
>> case NVM_DEV_REMOVE:
>> return nvm_ioctl_dev_remove(file, argp);
>> + case NVM_DEV_LUNS_STATUS:
>> + return nvm_ioctl_dev_luns_status(file, argp);
>> case NVM_DEV_INIT:
>> return nvm_ioctl_dev_init(file, argp);
>> case NVM_DEV_FACTORY:
>> diff --git a/drivers/lightnvm/gennvm.c b/drivers/lightnvm/gennvm.c
>> index 72e124a..b2390f4 100644
>> --- a/drivers/lightnvm/gennvm.c
>> +++ b/drivers/lightnvm/gennvm.c
>> @@ -502,6 +502,39 @@ static struct nvm_lun *gennvm_get_lun(struct nvm_dev
>> *dev, int lunid)
>> return &gn->luns[lunid].vlun;
>> }
>>
>> +static void gennvm_get_luns_status(struct nvm_dev *dev,
>> + struct nvm_ioctl_luns_status *status)
>> +{
>> + int i, lun_begin = status->lun_begin;
>> + int nr_luns, lun_end = status->lun_end;
>> + struct gen_nvm *gn = dev->mp;
>> + struct nvm_lun_status *lun_stat;
>> + struct gen_lun *lun;
>> +
>> + status->nr_luns = dev->nr_luns;
>> + nr_luns = min(lun_end - lun_begin + 1,
>> + NVM_LUNS_STATUS);
>> +
>> + for (i = 0; i < nr_luns; i++) {
>> + lun = &gn->luns[i + lun_begin];
>> + lun_stat = &status->status[i];
>> +
>> + lun_stat->reserved =
>> + test_bit(i + lun_begin, dev->lun_map);
>> + lun_stat->id = lun->vlun.id;
>> + lun_stat->lun_id = lun->vlun.lun_id;
>> + lun_stat->chnl_id = lun->vlun.chnl_id;
>> + lun_stat->nr_free_blocks =
>> + lun->vlun.nr_free_blocks;
>> + lun_stat->nr_open_blocks =
>> + lun->vlun.nr_open_blocks;
>> + lun_stat->nr_closed_blocks =
>> + lun->vlun.nr_closed_blocks;
>> + lun_stat->nr_bad_blocks =
>> + lun->vlun.nr_bad_blocks;
>> + }
>> +}
>> +
>> static void gennvm_lun_info_print(struct nvm_dev *dev)
>> {
>> struct gen_nvm *gn = dev->mp;
>> @@ -542,6 +575,7 @@ static struct nvmm_type gennvm = {
>> .get_lun = gennvm_get_lun,
>> .reserve_lun = gennvm_reserve_lun,
>> .release_lun = gennvm_release_lun,
>> + .get_luns_status = gennvm_get_luns_status,
>> .lun_info_print = gennvm_lun_info_print,
>>
>> .get_area = gennvm_get_area,
>> diff --git a/include/linux/lightnvm.h b/include/linux/lightnvm.h
>> index b941a8c..88b95f9 100644
>> --- a/include/linux/lightnvm.h
>> +++ b/include/linux/lightnvm.h
>> @@ -472,6 +472,8 @@ typedef int (nvmm_erase_blk_fn)(struct nvm_dev *,
>> struct nvm_block *,
>> typedef struct nvm_lun *(nvmm_get_lun_fn)(struct nvm_dev *, int);
>> typedef int (nvmm_reserve_lun)(struct nvm_dev *, int);
>> typedef void (nvmm_release_lun)(struct nvm_dev *, int);
>> +typedef void (nvmm_get_luns_status)(struct nvm_dev *,
>> + struct nvm_ioctl_luns_status *);
>> typedef void (nvmm_lun_info_print_fn)(struct nvm_dev *);
>>
>> typedef int (nvmm_get_area_fn)(struct nvm_dev *, sector_t *, sector_t);
>> @@ -502,6 +504,7 @@ struct nvmm_type {
>> nvmm_release_lun *release_lun;
>>
>> /* Statistics */
>> + nvmm_get_luns_status *get_luns_status;
>> nvmm_lun_info_print_fn *lun_info_print;
>>
>> nvmm_get_area_fn *get_area;
>> diff --git a/include/uapi/linux/lightnvm.h b/include/uapi/linux/lightnvm.h
>> index 6dbf6a0..2d52d6d 100644
>> --- a/include/uapi/linux/lightnvm.h
>> +++ b/include/uapi/linux/lightnvm.h
>> @@ -36,6 +36,7 @@
>> #define NVM_MMTYPE_LEN 8
>>
>> #define NVM_LUNS_MAX 768
>> +#define NVM_LUNS_STATUS 64
>>
>> #define NVM_CTRL_FILE "/dev/lightnvm/control"
>>
>> @@ -110,6 +111,25 @@ struct nvm_ioctl_remove {
>> __u32 flags;
>> };
>>
>> +struct nvm_lun_status {
>> + bool reserved;
>> + __u32 id;
>> + __u32 lun_id;
>> + __u32 chnl_id;
>> + __u32 nr_open_blocks;
>> + __u32 nr_closed_blocks;
>> + __u32 nr_free_blocks;
>> + __u32 nr_bad_blocks;
>> +};
>> +
>> +struct nvm_ioctl_luns_status {
>> + char dev[DISK_NAME_LEN];
>> + __u32 nr_luns;
>> + __u32 lun_begin;
>> + __u32 lun_end;
>> + struct nvm_lun_status status[NVM_LUNS_STATUS];
>> +};
>> +
>> struct nvm_ioctl_dev_init {
>> char dev[DISK_NAME_LEN]; /* open-channel SSD device
>> */
>> char mmtype[NVM_MMTYPE_LEN]; /* register to media
>> manager */
>> @@ -140,6 +160,7 @@ enum {
>> /* device level cmds */
>> NVM_DEV_CREATE_CMD,
>> NVM_DEV_REMOVE_CMD,
>> + NVM_DEV_LUNS_STATUS_CMD,
>>
>> /* Init a device to support LightNVM media managers */
>> NVM_DEV_INIT_CMD,
>> @@ -158,6 +179,8 @@ enum {
>> struct nvm_ioctl_create)
>> #define NVM_DEV_REMOVE _IOW(NVM_IOCTL,
>> NVM_DEV_REMOVE_CMD, \
>> struct nvm_ioctl_remove)
>> +#define NVM_DEV_LUNS_STATUS _IOW(NVM_IOCTL, NVM_DEV_LUNS_STATUS_CMD, \
>> + struct
>> nvm_ioctl_luns_status)
>> #define NVM_DEV_INIT _IOW(NVM_IOCTL, NVM_DEV_INIT_CMD, \
>> struct nvm_ioctl_dev_init)
>> #define NVM_DEV_FACTORY _IOW(NVM_IOCTL,
>> NVM_DEV_FACTORY_CMD, \
>>
>
> I think it will be better to expose this through sysfs. There is a patch
> coming up that will add support and enable us to get the luns.
>