nfit, address-range-scrub: determine one platform max_ars value

acpi_nfit_query_poison() is awkward in that it requires an nfit_spa
argument in order to determine what max_ars value to use. Instead probe
for the minimum max_ars across all scrub-capable ranges in the system
and drop the nfit_spa argument.

This enables a larger rework / simplification of the ARS state machine
whereby the status can be retrieved once and then iterated over all
address ranges to reap completions.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index 9c56022..866853a 100644 (file)
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -2494,16 +2494,16 @@ static int ars_get_status(struct acpi_nfit_desc *acpi_desc)
        int rc, cmd_rc;
 
        rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_STATUS, ars_status,
-                       acpi_desc->ars_status_size, &cmd_rc);
+                       acpi_desc->max_ars, &cmd_rc);
        if (rc < 0)
                return rc;
        return cmd_rc;
 }
 
-static int ars_status_process_records(struct acpi_nfit_desc *acpi_desc,
-               struct nd_cmd_ars_status *ars_status)
+static int ars_status_process_records(struct acpi_nfit_desc *acpi_desc)
 {
        struct nvdimm_bus *nvdimm_bus = acpi_desc->nvdimm_bus;
+       struct nd_cmd_ars_status *ars_status = acpi_desc->ars_status;
        int rc;
        u32 i;
 
@@ -2739,60 +2739,35 @@ static int acpi_nfit_register_region(struct acpi_nfit_desc *acpi_desc,
        return rc;
 }
 
-static int ars_status_alloc(struct acpi_nfit_desc *acpi_desc,
-               u32 max_ars)
+static int ars_status_alloc(struct acpi_nfit_desc *acpi_desc)
 {
        struct device *dev = acpi_desc->dev;
        struct nd_cmd_ars_status *ars_status;
 
-       if (acpi_desc->ars_status && acpi_desc->ars_status_size >= max_ars) {
-               memset(acpi_desc->ars_status, 0, acpi_desc->ars_status_size);
+       if (acpi_desc->ars_status) {
+               memset(acpi_desc->ars_status, 0, acpi_desc->max_ars);
                return 0;
        }
 
-       if (acpi_desc->ars_status)
-               devm_kfree(dev, acpi_desc->ars_status);
-       acpi_desc->ars_status = NULL;
-       ars_status = devm_kzalloc(dev, max_ars, GFP_KERNEL);
+       ars_status = devm_kzalloc(dev, acpi_desc->max_ars, GFP_KERNEL);
        if (!ars_status)
                return -ENOMEM;
        acpi_desc->ars_status = ars_status;
-       acpi_desc->ars_status_size = max_ars;
        return 0;
 }
 
-static int acpi_nfit_query_poison(struct acpi_nfit_desc *acpi_desc,
-               struct nfit_spa *nfit_spa)
+static int acpi_nfit_query_poison(struct acpi_nfit_desc *acpi_desc)
 {
-       struct acpi_nfit_system_address *spa = nfit_spa->spa;
        int rc;
 
-       if (!nfit_spa->max_ars) {
-               struct nd_cmd_ars_cap ars_cap;
-
-               memset(&ars_cap, 0, sizeof(ars_cap));
-               rc = ars_get_cap(acpi_desc, &ars_cap, nfit_spa);
-               if (rc < 0)
-                       return rc;
-               nfit_spa->max_ars = ars_cap.max_ars_out;
-               nfit_spa->clear_err_unit = ars_cap.clear_err_unit;
-               /* check that the supported scrub types match the spa type */
-               if (nfit_spa_type(spa) == NFIT_SPA_VOLATILE &&
-                               ((ars_cap.status >> 16) & ND_ARS_VOLATILE) == 0)
-                       return -ENOTTY;
-               else if (nfit_spa_type(spa) == NFIT_SPA_PM &&
-                               ((ars_cap.status >> 16) & ND_ARS_PERSISTENT) == 0)
-                       return -ENOTTY;
-       }
-
-       if (ars_status_alloc(acpi_desc, nfit_spa->max_ars))
+       if (ars_status_alloc(acpi_desc))
                return -ENOMEM;
 
        rc = ars_get_status(acpi_desc);
        if (rc < 0 && rc != -ENOSPC)
                return rc;
 
-       if (ars_status_process_records(acpi_desc, acpi_desc->ars_status))
+       if (ars_status_process_records(acpi_desc))
                return -ENOMEM;
 
        return 0;
@@ -2824,7 +2799,7 @@ static void acpi_nfit_async_scrub(struct acpi_nfit_desc *acpi_desc,
 
                if (acpi_desc->cancel)
                        break;
-               rc = acpi_nfit_query_poison(acpi_desc, nfit_spa);
+               rc = acpi_nfit_query_poison(acpi_desc);
                if (rc == -ENOTTY)
                        break;
                if (rc == -EBUSY && !tmo) {
@@ -2925,7 +2900,7 @@ static void acpi_nfit_scrub(struct work_struct *work)
                         */
                        rc = 0;
                } else
-                       rc = acpi_nfit_query_poison(acpi_desc, nfit_spa);
+                       rc = acpi_nfit_query_poison(acpi_desc);
 
                if (rc == -ENOTTY) {
                        /* no ars capability, just register spa and move on */
@@ -3018,6 +2993,31 @@ static void acpi_nfit_scrub(struct work_struct *work)
        mutex_unlock(&acpi_desc->init_mutex);
 }
 
+static void acpi_nfit_init_ars(struct acpi_nfit_desc *acpi_desc,
+               struct nfit_spa *nfit_spa)
+{
+       int type = nfit_spa_type(nfit_spa->spa);
+       struct nd_cmd_ars_cap ars_cap;
+       int rc;
+
+       memset(&ars_cap, 0, sizeof(ars_cap));
+       rc = ars_get_cap(acpi_desc, &ars_cap, nfit_spa);
+       if (rc < 0)
+               return;
+       /* check that the supported scrub types match the spa type */
+       if (type == NFIT_SPA_VOLATILE && ((ars_cap.status >> 16)
+                               & ND_ARS_VOLATILE) == 0)
+               return;
+       if (type == NFIT_SPA_PM && ((ars_cap.status >> 16)
+                               & ND_ARS_PERSISTENT) == 0)
+               return;
+
+       nfit_spa->max_ars = ars_cap.max_ars_out;
+       nfit_spa->clear_err_unit = ars_cap.clear_err_unit;
+       acpi_desc->max_ars = max(nfit_spa->max_ars, acpi_desc->max_ars);
+}
+
+
 static int acpi_nfit_register_regions(struct acpi_nfit_desc *acpi_desc)
 {
        struct nfit_spa *nfit_spa;
@@ -3026,8 +3026,10 @@ static int acpi_nfit_register_regions(struct acpi_nfit_desc *acpi_desc)
                int rc, type = nfit_spa_type(nfit_spa->spa);
 
                /* PMEM and VMEM will be registered by the ARS workqueue */
-               if (type == NFIT_SPA_PM || type == NFIT_SPA_VOLATILE)
+               if (type == NFIT_SPA_PM || type == NFIT_SPA_VOLATILE) {
+                       acpi_nfit_init_ars(acpi_desc, nfit_spa);
                        continue;
+               }
                /* BLK apertures belong to BLK region registration below */
                if (type == NFIT_SPA_BDW)
                        continue;

diff --git a/drivers/acpi/nfit/nfit.h b/drivers/acpi/nfit/nfit.h
index 2b97e5f..45e7949 100644 (file)
--- a/drivers/acpi/nfit/nfit.h
+++ b/drivers/acpi/nfit/nfit.h
@@ -197,10 +197,10 @@ struct acpi_nfit_desc {
        struct device *dev;
        u8 ars_start_flags;
        struct nd_cmd_ars_status *ars_status;
-       size_t ars_status_size;
        struct work_struct work;
        struct list_head list;
        struct kernfs_node *scrub_count_state;
+       unsigned int max_ars;
        unsigned int scrub_count;
        unsigned int scrub_mode;
        unsigned int cancel:1;