Adding a flag for nvdimm->flags to support erase functions. While it's ok
to hold the nvdimm_bus lock for secure erase due to minimal time to execute
the command, overwrite requires a significantly longer time and makes this
impossible. The flag will block any drivers from being loaded and DIMMs
being probed.

Signed-off-by: Dave Jiang <[email protected]>
---
 drivers/nvdimm/dimm_devs.c   |    6 ++++++
 drivers/nvdimm/nd-core.h     |   16 ++++++++++++++++
 drivers/nvdimm/region_devs.c |    7 +++++++
 drivers/nvdimm/security.c    |   18 ++++++++++++++++++
 include/linux/libnvdimm.h    |    2 ++
 5 files changed, 49 insertions(+)

diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c
index e3b46849ee0a..bfdc4824ba11 100644
--- a/drivers/nvdimm/dimm_devs.c
+++ b/drivers/nvdimm/dimm_devs.c
@@ -557,6 +557,12 @@ int nvdimm_security_freeze(struct nvdimm *nvdimm)
        if (nvdimm->sec.state < 0)
                return -EIO;
 
+       rc = nvdimm_security_check_busy(nvdimm);
+       if (rc < 0) {
+               dev_warn(&nvdimm->dev, "Security operation in progress.\n");
+               return rc;
+       }
+
        rc = nvdimm->sec.ops->freeze(nvdimm);
        nvdimm->sec.state = nvdimm_security_state(nvdimm);
 
diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h
index 3c8cdd40c456..353f945cda5b 100644
--- a/drivers/nvdimm/nd-core.h
+++ b/drivers/nvdimm/nd-core.h
@@ -61,6 +61,22 @@ int nvdimm_security_disable(struct nvdimm *nvdimm, unsigned 
int keyid);
 int nvdimm_security_update(struct nvdimm *nvdimm, unsigned int keyid,
                unsigned int new_keyid);
 int nvdimm_security_erase(struct nvdimm *nvdimm, unsigned int keyid);
+static inline int nvdimm_security_check_busy(struct nvdimm *nvdimm)
+{
+       if (test_bit(NDD_SECURITY_BUSY, &nvdimm->flags))
+               return -EBUSY;
+       return 0;
+}
+
+static inline void nvdimm_set_security_busy(struct nvdimm *nvdimm)
+{
+       set_bit(NDD_SECURITY_BUSY, &nvdimm->flags);
+}
+
+static inline void nvdimm_clear_security_busy(struct nvdimm *nvdimm)
+{
+       clear_bit(NDD_SECURITY_BUSY, &nvdimm->flags);
+}
 
 /**
  * struct blk_alloc_info - tracking info for BLK dpa scanning
diff --git a/drivers/nvdimm/region_devs.c b/drivers/nvdimm/region_devs.c
index 174a418cb171..7ccca49c7a52 100644
--- a/drivers/nvdimm/region_devs.c
+++ b/drivers/nvdimm/region_devs.c
@@ -78,6 +78,13 @@ int nd_region_activate(struct nd_region *nd_region)
        for (i = 0; i < nd_region->ndr_mappings; i++) {
                struct nd_mapping *nd_mapping = &nd_region->mapping[i];
                struct nvdimm *nvdimm = nd_mapping->nvdimm;
+               int rc;
+
+               rc = nvdimm_security_check_busy(nvdimm);
+               if (rc) {
+                       nvdimm_bus_unlock(&nd_region->dev);
+                       return rc;
+               }
 
                /* at least one null hint slot per-dimm for the "no-hint" case 
*/
                flush_data_size += sizeof(void *);
diff --git a/drivers/nvdimm/security.c b/drivers/nvdimm/security.c
index 4836f2fda271..5a03dffd0056 100644
--- a/drivers/nvdimm/security.c
+++ b/drivers/nvdimm/security.c
@@ -143,6 +143,12 @@ static int __nvdimm_security_unlock(struct nvdimm *nvdimm)
                        || nvdimm->sec.state < 0)
                return -EIO;
 
+       rc = nvdimm_security_check_busy(nvdimm);
+       if (rc < 0) {
+               dev_warn(dev, "Security operation in progress.\n");
+               return rc;
+       }
+
        /*
         * If the pre-OS has unlocked the DIMM, attempt to send the key
         * from request_key() to the hardware for verification.  Failure
@@ -203,6 +209,12 @@ int nvdimm_security_disable(struct nvdimm *nvdimm, 
unsigned int keyid)
                return -EIO;
        }
 
+       rc = nvdimm_security_check_busy(nvdimm);
+       if (rc < 0) {
+               dev_warn(dev, "Security operation in progress.\n");
+               return rc;
+       }
+
        key = nvdimm_lookup_user_key(nvdimm, keyid, NVDIMM_BASE_KEY);
        if (!key)
                return -ENOKEY;
@@ -288,6 +300,12 @@ int nvdimm_security_erase(struct nvdimm *nvdimm, unsigned 
int keyid)
                return -EIO;
        }
 
+       rc = nvdimm_security_check_busy(nvdimm);
+       if (rc < 0) {
+               dev_warn(dev, "Security operation in progress.\n");
+               return rc;
+       }
+
        key = nvdimm_lookup_user_key(nvdimm, keyid, NVDIMM_BASE_KEY);
        if (!key)
                return -ENOKEY;
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index 9a6cb7067dc7..8507d2896ae0 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -38,6 +38,8 @@ enum {
        NDD_UNARMED = 1,
        /* locked memory devices should not be accessed */
        NDD_LOCKED = 2,
+       /* memory under security wipes should not be accessed */
+       NDD_SECURITY_BUSY = 3,
 
        /* need to set a limit somewhere, but yes, this is likely overkill */
        ND_IOCTL_MAX_BUFLEN = SZ_4M,

_______________________________________________
Linux-nvdimm mailing list
[email protected]
https://lists.01.org/mailman/listinfo/linux-nvdimm

Reply via email to