lkml.org 
[lkml]   [2017]   [Jun]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRE: [PATCH v2] libnvdimm, pmem: Add sysfs notifications to badblocks
Date
> > Sysfs "badblocks" information may be updated during run-time that:
> > - MCE, SCI, and sysfs "scrub" may add new bad blocks
> > - Writes and ioctl() may clear bad blocks
> >
> > Add support to send sysfs notifications to sysfs "badblocks" file
> > under region and pmem directories when their badblocks information
> > is re-evaluated (but is not necessarily changed) during run-time.
> >
> > Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
> > Cc: Dan Williams <dan.j.williams@intel.com>
> > Cc: Vishal Verma <vishal.l.verma@intel.com>
> > Cc: Linda Knippers <linda.knippers@hpe.com>
> > ---
> > v2: Send notifications for the clearing case
> > ---
> > drivers/nvdimm/bus.c | 3 +++
> > drivers/nvdimm/nd.h | 1 +
> > drivers/nvdimm/pmem.c | 14 ++++++++++++++
> > drivers/nvdimm/pmem.h | 1 +
> > drivers/nvdimm/region.c | 12 ++++++++++--
> > 5 files changed, 29 insertions(+), 2 deletions(-)
> >
> [..]
> > diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
> > index c544d46..6c14c72 100644
> > --- a/drivers/nvdimm/pmem.c
> > +++ b/drivers/nvdimm/pmem.c
> [..]
> > @@ -377,6 +379,13 @@ static int pmem_attach_disk(struct device *dev,
> >
> > revalidate_disk(disk);
> >
> > + pmem->bb_state = sysfs_get_dirent(disk_to_dev(disk)->kobj.sd,
> > + "badblocks");
> > + if (pmem->bb_state)
> > + sysfs_put(pmem->bb_state);
>
> Sorry I missed this on the first review, but this looks broken. We
> need to hold the reference for as long as we might trigger
> notifications, so the sysfs_put() should wait until
> pmem_release_disk().

I see.

> [..]
> > diff --git a/drivers/nvdimm/region.c b/drivers/nvdimm/region.c
> > index 869a886..ca94029 100644
> > --- a/drivers/nvdimm/region.c
> > +++ b/drivers/nvdimm/region.c
> > @@ -58,10 +58,16 @@ static int nd_region_probe(struct device *dev)
> >
> > if (devm_init_badblocks(dev, &nd_region->bb))
> > return -ENODEV;
> > + nd_region->bb_state = sysfs_get_dirent(nd_region->dev.kobj.sd,
> > + "badblocks");
> > + if (nd_region->bb_state)
> > + sysfs_put(nd_region->bb_state);
>
> ...same here. This should wait until we tear down the region.
>
> I'll take a look at an incremental fix patch.

Thanks Dan!
-Toshi

\
 
 \ /
  Last update: 2017-07-01 02:42    [W:0.104 / U:6.968 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site