Re: [PATCH 2/2 v2] scsi: ufs: use sysfs entry for health info
From: Jaegeuk Kim
Date: Wed Dec 20 2017 - 14:33:48 EST
On 12/20, gregkh@xxxxxxxxxxxxxxxxxxx wrote:
> On Tue, Dec 19, 2017 at 02:46:44PM -0800, Jaegeuk Kim wrote:
> > >From 3368207da5988b8fed4e41e6c0f49a60ac014222 Mon Sep 17 00:00:00 2001
> > From: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> > Date: Tue, 26 Sep 2017 20:53:48 -0700
> > Subject: [PATCH 2/2] scsi: ufs: introduce sysfs entries exposing UFS health
> > info
> >
> > This patch adds a new sysfs group, namely health, via:
> >
> > /sys/devices/soc/X.ufshc/health/
> >
> > This directory contains the below entries, each of which shows an 8-bytes
> > hex number representing different meanings defined by JEDEC specfication.
> >
> > Users can simply read these entries to check how their underlying flash
> > storage is getting reached out to its end of life. For example, if
> > lifetimeA shows 0xb, it would be the right time to consider device swap.
> >
> > - length
> > : must be 25h
> >
> > - type
> > : must be 09h
> >
> > - eol
> > 00h: Not defined
> > 01h: Normal
> > 02h: Warning
> > 03h: Critical
> >
> > - lifetimeA/B
> > 00h: Not defined
> > 01h: 0% ~ 10% device life time used
> > 02h: 10% ~ 20% device life time used
> > 03h: 20% ~ 30% device life time used
> > 04h: 30% ~ 40% device life time used
> > 05h: 40% ~ 50% device life time used
> > 06h: 50% ~ 60% device life time used
> > 07h: 60% ~ 70% device life time used
> > 08h: 70% ~ 80% device life time used
> > 09h: 80% ~ 90% device life time used
> > 0Ah: 90% ~ 100% device life time used
> > 0Bh: Exceeded its maximum estimated device life time
> >
> > Cc: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>
> > Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> > ---
> > Documentation/ABI/testing/sysfs-devices-soc-ufs | 25 +++++++++
> > MAINTAINERS | 1 +
> > drivers/scsi/ufs/ufs.h | 2 +
> > drivers/scsi/ufs/ufshcd.c | 69 ++++++++++++++++++++++++-
> > drivers/scsi/ufs/ufshcd.h | 1 +
> > 5 files changed, 97 insertions(+), 1 deletion(-)
> > create mode 100644 Documentation/ABI/testing/sysfs-devices-soc-ufs
> >
> > diff --git a/Documentation/ABI/testing/sysfs-devices-soc-ufs b/Documentation/ABI/testing/sysfs-devices-soc-ufs
> > new file mode 100644
> > index 000000000000..313771a383e4
> > --- /dev/null
> > +++ b/Documentation/ABI/testing/sysfs-devices-soc-ufs
> > @@ -0,0 +1,25 @@
> > +What: /sys/devices/soc/X.ufshc/health
> > +Date: September 2017
> > +contact: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> > +Description:
> > + This directory contains health information reported by UFS.
> > + - length must be 25h
> > + - type must be 09h
> > + - eol represent
> > + 00h: Not defined
> > + 01h: Normal
> > + 02h: Warning
> > + 03h: Critical
> > + - lifetimeA/B
> > + 00h: Not defined
> > + 01h: 0% ~ 10% device life time used
> > + 02h: 10% ~ 20% device life time used
> > + 03h: 20% ~ 30% device life time used
> > + 04h: 30% ~ 40% device life time used
> > + 05h: 40% ~ 50% device life time used
> > + 06h: 50% ~ 60% device life time used
> > + 07h: 60% ~ 70% device life time used
> > + 08h: 70% ~ 80% device life time used
> > + 09h: 80% ~ 90% device life time used
> > + 0Ah: 90% ~ 100% device life time used
> > + 0Bh: Exceeded its maximum estimated device life time
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index aa71ab52fd76..947034319bb4 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -13999,6 +13999,7 @@ M: Vinayak Holikatti <vinholikatti@xxxxxxxxx>
> > L: linux-scsi@xxxxxxxxxxxxxxx
> > S: Supported
> > F: Documentation/scsi/ufs.txt
> > +F: Documentation/ABI/testing/sysfs-devices-soc-ufs
> > F: drivers/scsi/ufs/
> >
> > UNIVERSAL FLASH STORAGE HOST CONTROLLER DRIVER DWC HOOKS
> > diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
> > index 54deeb754db5..1af541d56c7d 100644
> > --- a/drivers/scsi/ufs/ufs.h
> > +++ b/drivers/scsi/ufs/ufs.h
> > @@ -154,6 +154,7 @@ enum desc_idn {
> > QUERY_DESC_IDN_RFU_1 = 0x6,
> > QUERY_DESC_IDN_GEOMETRY = 0x7,
> > QUERY_DESC_IDN_POWER = 0x8,
> > + QUERY_DESC_IDN_HEALTH = 0x9,
> > QUERY_DESC_IDN_MAX,
> > };
> >
> > @@ -169,6 +170,7 @@ enum ufs_desc_def_size {
> > QUERY_DESC_INTERCONNECT_DEF_SIZE = 0x06,
> > QUERY_DESC_GEOMETRY_DEF_SIZE = 0x44,
> > QUERY_DESC_POWER_DEF_SIZE = 0x62,
> > + QUERY_DESC_HEALTH_DEF_SIZE = 0x25,
> > };
> >
> > /* Unit descriptor parameters offsets in bytes*/
> > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> > index 12ff7daebb00..5cbb08fff0f4 100644
> > --- a/drivers/scsi/ufs/ufshcd.c
> > +++ b/drivers/scsi/ufs/ufshcd.c
> > @@ -2991,6 +2991,9 @@ int ufshcd_map_desc_id_to_length(struct ufs_hba *hba,
> > case QUERY_DESC_IDN_RFU_1:
> > *desc_len = 0;
> > break;
> > + case QUERY_DESC_IDN_HEALTH:
> > + *desc_len = hba->desc_size.health_desc;
> > + break;
> > default:
> > *desc_len = 0;
> > return -EINVAL;
> > @@ -6298,6 +6301,11 @@ static void ufshcd_init_desc_sizes(struct ufs_hba *hba)
> > &hba->desc_size.geom_desc);
> > if (err)
> > hba->desc_size.geom_desc = QUERY_DESC_GEOMETRY_DEF_SIZE;
> > +
> > + err = ufshcd_read_desc_length(hba, QUERY_DESC_IDN_HEALTH, 0,
> > + &hba->desc_size.health_desc);
> > + if (err)
> > + hba->desc_size.health_desc = QUERY_DESC_HEALTH_DEF_SIZE;
> > }
> >
> > static void ufshcd_def_desc_sizes(struct ufs_hba *hba)
> > @@ -6308,6 +6316,7 @@ static void ufshcd_def_desc_sizes(struct ufs_hba *hba)
> > hba->desc_size.conf_desc = QUERY_DESC_CONFIGURATION_DEF_SIZE;
> > hba->desc_size.unit_desc = QUERY_DESC_UNIT_DEF_SIZE;
> > hba->desc_size.geom_desc = QUERY_DESC_GEOMETRY_DEF_SIZE;
> > + hba->desc_size.health_desc = QUERY_DESC_HEALTH_DEF_SIZE;
> > }
> >
> > /**
> > @@ -7688,14 +7697,72 @@ static const struct attribute_group ufshcd_attr_group = {
> > .attrs = ufshcd_attrs,
> > };
> >
> > +struct health_attr {
> > + struct attribute attr;
> > + ssize_t (*show)(struct device *dev,
> > + struct health_attr *attr, char *buf);
> > + int byte_offset;
> > +};
> > +
> > +static ssize_t health_attr_show(struct device *dev,
> > + struct health_attr *attr, char *buf)
> > +{
> > + struct ufs_hba *hba = dev_get_drvdata(dev);
> > + int buff_len = hba->desc_size.health_desc;
> > + u8 desc_buf[hba->desc_size.health_desc];
> > + int err;
> > +
> > + if (attr->byte_offset >= buff_len)
> > + return 0;
> > +
> > + pm_runtime_get_sync(hba->dev);
> > + err = ufshcd_read_desc(hba, QUERY_DESC_IDN_HEALTH, 0,
> > + desc_buf, buff_len);
> > + pm_runtime_put_sync(hba->dev);
> > + if (err)
> > + return 0;
> > +
> > + return scnprintf(buf, PAGE_SIZE, "0x%02x", desc_buf[attr->byte_offset]);
> > +}
> > +
> > +#define HEALTH_ATTR_RO(_name, _byte_offset) \
> > +static struct health_attr ufs_health_##_name = { \
> > + .attr = {.name = __stringify(_name), .mode = 0444}, \
> > + .show = health_attr_show, \
> > + .byte_offset = _byte_offset, \
> > +}
>
> This is a nice "hack" to make things simpler, but I worry about not
> using the "normal" __ATTR_* macros here. But I can't think of a simpler
> way to do this now, except if you had a table of strings and offsets
> that you then used to look up to get the offset based on the name of the
> attribute.
I gave it a try to use DEVICE_ATTR_RO() in v3, so could you please take a look
at it?
Thanks,
>
> Anyway, nice job, I'm just rambling:
>
> Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>