nfit, address-range-scrub: fix scrub in-progress reporting

There is a small window whereby ARS scan requests can schedule work that
userspace will miss when polling scrub_show. Hold the init_mutex lock
over calls to report the status to close this potential escape. Also,
make sure that requests to cancel the ARS workqueue are treated as an
idle event.

Cc: <stable@vger.kernel.org>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Fixes: 37b137ff8c ("nfit, libnvdimm: allow an ARS scrub...")
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Dan Williams 2018-04-02 16:40:04 -07:00
parent 8d0d8ed335
commit 78727137fd
1 changed files with 4 additions and 1 deletions

View File

@ -1249,8 +1249,11 @@ static ssize_t scrub_show(struct device *dev,
if (nd_desc) {
struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc);
mutex_lock(&acpi_desc->init_mutex);
rc = sprintf(buf, "%d%s", acpi_desc->scrub_count,
(work_busy(&acpi_desc->work)) ? "+\n" : "\n");
work_busy(&acpi_desc->work)
&& !acpi_desc->cancel ? "+\n" : "\n");
mutex_unlock(&acpi_desc->init_mutex);
}
device_unlock(dev);
return rc;