[PATCH v7 18/20] cxl: bypass cpu_cache_invalidate_memregion() when in test config

[Dave Jiang]

Bypass cpu_cache_invalidate_memregion() and checks when doing testing
using CONFIG_NVDIMM_SECURITY_TEST flag. The bypass allows testing on
QEMU where cpu_cache_has_invalidate_memregion() fails. Usage of
cpu_cache_invalidate_memregion() is not needed for cxl_test security
testing.

Signed-off-by: Dave Jiang <dave.ji...@intel.com>
---
 drivers/cxl/security.c |   35 ++++++++++++++++++++++++++++++-----
 1 file changed, 30 insertions(+), 5 deletions(-)

diff --git a/drivers/cxl/security.c b/drivers/cxl/security.c
index cbd005ceb091..2b5088af8fc4 100644
--- a/drivers/cxl/security.c
+++ b/drivers/cxl/security.c
@@ -111,6 +111,31 @@ static int cxl_pmem_security_freeze(struct nvdimm *nvdimm)
        return cxl_mbox_send_cmd(cxlds, CXL_MBOX_OP_FREEZE_SECURITY, NULL, 0, 
NULL, 0);
 }
 
+static bool cxl_has_invalidate_memregion(struct cxl_nvdimm *cxl_nvd)
+{
+       if (!cpu_cache_has_invalidate_memregion()) {
+               if (IS_ENABLED(CONFIG_NVDIMM_SECURITY_TEST)) {
+                       dev_warn_once(&cxl_nvd->dev,
+                                     "Bypassing 
cpu_cache_has_invalidate_memregion() check for testing!\n");
+                       return true;
+               }
+               return false;
+       }
+
+       return true;
+}
+
+static void cxl_invalidate_memregion(struct cxl_nvdimm *cxl_nvd)
+{
+       if (IS_ENABLED(CONFIG_NVDIMM_SECURITY_TEST)) {
+               dev_warn_once(&cxl_nvd->dev,
+                             "Bypassing cpu_cache_invalidate_memergion() for 
testing!\n");
+               return;
+       }
+
+       cpu_cache_invalidate_memregion(IORES_DESC_PERSISTENT_MEMORY);
+}
+
 static int cxl_pmem_security_unlock(struct nvdimm *nvdimm,
                                    const struct nvdimm_key_data *key_data)
 {
@@ -120,7 +145,7 @@ static int cxl_pmem_security_unlock(struct nvdimm *nvdimm,
        u8 pass[NVDIMM_PASSPHRASE_LEN];
        int rc;
 
-       if (!cpu_cache_has_invalidate_memregion())
+       if (!cxl_has_invalidate_memregion(cxl_nvd))
                return -EINVAL;
 
        memcpy(pass, key_data->data, NVDIMM_PASSPHRASE_LEN);
@@ -130,7 +155,7 @@ static int cxl_pmem_security_unlock(struct nvdimm *nvdimm,
                return rc;
 
        /* DIMM unlocked, invalidate all CPU caches before we read it */
-       cpu_cache_invalidate_memregion(IORES_DESC_PERSISTENT_MEMORY);
+       cxl_invalidate_memregion(cxl_nvd);
        return 0;
 }
 
@@ -144,21 +169,21 @@ static int cxl_pmem_security_passphrase_erase(struct 
nvdimm *nvdimm,
        struct cxl_pass_erase erase;
        int rc;
 
-       if (!cpu_cache_has_invalidate_memregion())
+       if (!cxl_has_invalidate_memregion(cxl_nvd))
                return -EINVAL;
 
        erase.type = ptype == NVDIMM_MASTER ?
                CXL_PMEM_SEC_PASS_MASTER : CXL_PMEM_SEC_PASS_USER;
        memcpy(erase.pass, key->data, NVDIMM_PASSPHRASE_LEN);
        /* Flush all cache before we erase mem device */
-       cpu_cache_invalidate_memregion(IORES_DESC_PERSISTENT_MEMORY);
+       cxl_invalidate_memregion(cxl_nvd);
        rc = cxl_mbox_send_cmd(cxlds, CXL_MBOX_OP_PASSPHRASE_SECURE_ERASE,
                               &erase, sizeof(erase), NULL, 0);
        if (rc < 0)
                return rc;
 
        /* mem device erased, invalidate all CPU caches before data is read */
-       cpu_cache_invalidate_memregion(IORES_DESC_PERSISTENT_MEMORY);
+       cxl_invalidate_memregion(cxl_nvd);
        return 0;
 }