libnvdimm, nfit: centralize command status translation

The return value from an 'ndctl_fn' reports the command execution
status, i.e. was the command properly formatted and was it successfully
submitted to the bus provider.  The new 'cmd_rc' parameter allows the bus
provider to communicate command specific results, translated into
common error codes.

Convert the ARS commands to this scheme to:

1/ Consolidate status reporting

2/ Prepare for for expanding ars unit test cases

3/ Make the implementation more generic

Cc: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
index 35947ac..4dd2b68 100644 (file)
--- a/drivers/acpi/nfit.c
+++ b/drivers/acpi/nfit.c
@@ -72,9 +72,80 @@ static struct acpi_device *to_acpi_dev(struct acpi_nfit_desc *acpi_desc)
        return to_acpi_device(acpi_desc->dev);
 }
 
+static int xlat_status(void *buf, unsigned int cmd)
+{
+       struct nd_cmd_ars_status *ars_status;
+       struct nd_cmd_ars_start *ars_start;
+       struct nd_cmd_ars_cap *ars_cap;
+       u16 flags;
+
+       switch (cmd) {
+       case ND_CMD_ARS_CAP:
+               ars_cap = buf;
+               if ((ars_cap->status & 0xffff) == NFIT_ARS_CAP_NONE)
+                       return -ENOTTY;
+
+               /* Command failed */
+               if (ars_cap->status & 0xffff)
+                       return -EIO;
+
+               /* No supported scan types for this range */
+               flags = ND_ARS_PERSISTENT | ND_ARS_VOLATILE;
+               if ((ars_cap->status >> 16 & flags) == 0)
+                       return -ENOTTY;
+               break;
+       case ND_CMD_ARS_START:
+               ars_start = buf;
+               /* ARS is in progress */
+               if ((ars_start->status & 0xffff) == NFIT_ARS_START_BUSY)
+                       return -EBUSY;
+
+               /* Command failed */
+               if (ars_start->status & 0xffff)
+                       return -EIO;
+               break;
+       case ND_CMD_ARS_STATUS:
+               ars_status = buf;
+               /* Command failed */
+               if (ars_status->status & 0xffff)
+                       return -EIO;
+               /* Check extended status (Upper two bytes) */
+               if (ars_status->status == NFIT_ARS_STATUS_DONE)
+                       return 0;
+
+               /* ARS is in progress */
+               if (ars_status->status == NFIT_ARS_STATUS_BUSY)
+                       return -EBUSY;
+
+               /* No ARS performed for the current boot */
+               if (ars_status->status == NFIT_ARS_STATUS_NONE)
+                       return -EAGAIN;
+
+               /*
+                * ARS interrupted, either we overflowed or some other
+                * agent wants the scan to stop.  If we didn't overflow
+                * then just continue with the returned results.
+                */
+               if (ars_status->status == NFIT_ARS_STATUS_INTR) {
+                       if (ars_status->flags & NFIT_ARS_F_OVERFLOW)
+                               return -ENOSPC;
+                       return 0;
+               }
+
+               /* Unknown status */
+               if (ars_status->status >> 16)
+                       return -EIO;
+               break;
+       default:
+               break;
+       }
+
+       return 0;
+}
+
 static int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc,
                struct nvdimm *nvdimm, unsigned int cmd, void *buf,
-               unsigned int buf_len)
+               unsigned int buf_len, int *cmd_rc)
 {
        struct acpi_nfit_desc *acpi_desc = to_acpi_nfit_desc(nd_desc);
        const struct nd_cmd_desc *desc = NULL;
@@ -185,6 +256,8 @@ static int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc,
                         * unfilled in the output buffer
                         */
                        rc = buf_len - offset - in_buf.buffer.length;
+                       if (cmd_rc)
+                               *cmd_rc = xlat_status(buf, cmd);
                } else {
                        dev_err(dev, "%s:%s underrun cmd: %s buf_len: %d out_len: %d\n",
                                        __func__, dimm_name, cmd_name, buf_len,
@@ -1105,7 +1178,7 @@ static void write_blk_ctl(struct nfit_blk *nfit_blk, unsigned int bw,
        writeq(cmd, mmio->addr.base + offset);
        wmb_blk(nfit_blk);
 
-       if (nfit_blk->dimm_flags & ND_BLK_DCR_LATCH)
+       if (nfit_blk->dimm_flags & NFIT_BLK_DCR_LATCH)
                readq(mmio->addr.base + offset);
 }
 
@@ -1141,7 +1214,7 @@ static int acpi_nfit_blk_single_io(struct nfit_blk *nfit_blk,
                        memcpy_to_pmem(mmio->addr.aperture + offset,
                                        iobuf + copied, c);
                else {
-                       if (nfit_blk->dimm_flags & ND_BLK_READ_FLUSH)
+                       if (nfit_blk->dimm_flags & NFIT_BLK_READ_FLUSH)
                                mmio_flush_range((void __force *)
                                        mmio->addr.aperture + offset, c);
 
@@ -1328,13 +1401,13 @@ static int acpi_nfit_blk_get_flags(struct nvdimm_bus_descriptor *nd_desc,
 
        memset(&flags, 0, sizeof(flags));
        rc = nd_desc->ndctl(nd_desc, nvdimm, ND_CMD_DIMM_FLAGS, &flags,
-                       sizeof(flags));
+                       sizeof(flags), NULL);
 
        if (rc >= 0 && flags.status == 0)
                nfit_blk->dimm_flags = flags.flags;
        else if (rc == -ENOTTY) {
                /* fall back to a conservative default */
-               nfit_blk->dimm_flags = ND_BLK_DCR_LATCH | ND_BLK_READ_FLUSH;
+               nfit_blk->dimm_flags = NFIT_BLK_DCR_LATCH | NFIT_BLK_READ_FLUSH;
                rc = 0;
        } else
                rc = -ENXIO;
@@ -1473,19 +1546,27 @@ static void acpi_nfit_blk_region_disable(struct nvdimm_bus *nvdimm_bus,
        /* devm will free nfit_blk */
 }
 
-static int ars_get_cap(struct nvdimm_bus_descriptor *nd_desc,
+static int ars_get_cap(struct acpi_nfit_desc *acpi_desc,
                struct nd_cmd_ars_cap *cmd, u64 addr, u64 length)
 {
+       struct nvdimm_bus_descriptor *nd_desc = &acpi_desc->nd_desc;
+       int cmd_rc, rc;
+
        cmd->address = addr;
        cmd->length = length;
-
-       return nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_CAP, cmd,
-                       sizeof(*cmd));
+       rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_CAP, cmd,
+                       sizeof(*cmd), &cmd_rc);
+       if (rc < 0)
+               return rc;
+       if (cmd_rc < 0)
+               return cmd_rc;
+       return 0;
 }
 
 static int ars_do_start(struct nvdimm_bus_descriptor *nd_desc,
                struct nd_cmd_ars_start *cmd, u64 addr, u64 length)
 {
+       int cmd_rc;
        int rc;
 
        cmd->address = addr;
@@ -1494,52 +1575,49 @@ static int ars_do_start(struct nvdimm_bus_descriptor *nd_desc,
 
        while (1) {
                rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_START, cmd,
-                               sizeof(*cmd));
-               if (rc)
+                               sizeof(*cmd), &cmd_rc);
+
+               if (rc < 0)
                        return rc;
-               switch (cmd->status) {
-               case 0:
-                       return 0;
-               case 1:
-                       /* ARS unsupported, but we should never get here */
-                       return 0;
-               case 6:
+
+               if (cmd_rc == -EBUSY) {
                        /* ARS is in progress */
                        msleep(1000);
-                       break;
-               default:
-                       return -ENXIO;
+                       continue;
                }
+
+               if (cmd_rc < 0)
+                       return cmd_rc;
+
+               return 0;
        }
 }
 
 static int ars_get_status(struct nvdimm_bus_descriptor *nd_desc,
                struct nd_cmd_ars_status *cmd, u32 size)
 {
-       int rc;
+       int rc, cmd_rc;
 
        while (1) {
                rc = nd_desc->ndctl(nd_desc, NULL, ND_CMD_ARS_STATUS, cmd,
-                       size);
-               if (rc || cmd->status & 0xffff)
-                       return -ENXIO;
+                       size, &cmd_rc);
+               if (rc < 0)
+                       return rc;
 
-               /* Check extended status (Upper two bytes) */
-               switch (cmd->status >> 16) {
-               case 0:
-                       return 0;
-               case 1:
-                       /* ARS is in progress */
+               /* FIXME make async and have a timeout */
+               if (cmd_rc == -EBUSY) {
                        msleep(1000);
-                       break;
-               case 2:
-                       /* No ARS performed for the current boot */
+                       continue;
+               }
+
+               if (cmd_rc == -EAGAIN || cmd_rc == 0)
                        return 0;
-               case 3:
-                       /* TODO: error list overflow support */
-               default:
+
+               /* TODO: error list overflow support */
+               if (cmd_rc == -ENOSPC)
                        return -ENXIO;
-               }
+
+               return cmd_rc;
        }
 }
 
@@ -1590,28 +1668,11 @@ static int acpi_nfit_find_poison(struct acpi_nfit_desc *acpi_desc,
        start = ndr_desc->res->start;
        len = ndr_desc->res->end - ndr_desc->res->start + 1;
 
-       /*
-        * If ARS is unimplemented, unsupported, or if the 'Persistent Memory
-        * Scrub' flag in extended status is not set, skip this but continue
-        * initialization
-        */
-       rc = ars_get_cap(nd_desc, ars_cap, start, len);
+       rc = ars_get_cap(acpi_desc, ars_cap, start, len);
        if (rc == -ENOTTY) {
-               dev_dbg(acpi_desc->dev,
-                       "Address Range Scrub is not implemented, won't create an error list\n");
                rc = 0;
                goto out;
        }
-       if (rc)
-               goto out;
-
-       if ((ars_cap->status & 0xffff) ||
-               !(ars_cap->status >> 16 & ND_ARS_PERSISTENT)) {
-               dev_warn(acpi_desc->dev,
-                       "ARS unsupported (status: 0x%x), won't create an error list\n",
-                       ars_cap->status);
-               goto out;
-       }
 
        /*
         * Check if a full-range ARS has been run. If so, use those results
@@ -1651,15 +1712,15 @@ static int acpi_nfit_find_poison(struct acpi_nfit_desc *acpi_desc,
                u64 done, end;
 
                rc = ars_do_start(nd_desc, ars_start, cur, remaining);
-               if (rc)
+               if (rc < 0)
                        goto out;
 
                rc = ars_get_status(nd_desc, ars_status, ars_status_size);
-               if (rc)
+               if (rc < 0)
                        goto out;
 
                rc = ars_status_process_records(nvdimm_bus, ars_status, cur);
-               if (rc)
+               if (rc < 0)
                        goto out;
 
                end = min(cur + remaining,

diff --git a/drivers/acpi/nfit.h b/drivers/acpi/nfit.h
index 6689b0a..f45b7d9 100644 (file)
--- a/drivers/acpi/nfit.h
+++ b/drivers/acpi/nfit.h
@@ -47,8 +47,15 @@ enum nfit_fic {
 };
 
 enum {
-       ND_BLK_READ_FLUSH = 1,
-       ND_BLK_DCR_LATCH = 2,
+       NFIT_BLK_READ_FLUSH = 1,
+       NFIT_BLK_DCR_LATCH = 2,
+       NFIT_ARS_STATUS_DONE = 0,
+       NFIT_ARS_STATUS_BUSY = 1 << 16,
+       NFIT_ARS_STATUS_NONE = 2 << 16,
+       NFIT_ARS_STATUS_INTR = 3 << 16,
+       NFIT_ARS_START_BUSY = 6,
+       NFIT_ARS_CAP_NONE = 1,
+       NFIT_ARS_F_OVERFLOW = 1,
 };
 
 struct nfit_spa {

diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index 5d28e94..c3ba888 100644 (file)
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -587,7 +587,7 @@ static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
        if (rc)
                goto out_unlock;
 
-       rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len);
+       rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len, NULL);
        if (rc < 0)
                goto out_unlock;
        if (copy_to_user(p, buf, buf_len))

diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c
index 651b8d1..c56f882 100644 (file)
--- a/drivers/nvdimm/dimm_devs.c
+++ b/drivers/nvdimm/dimm_devs.c
@@ -75,7 +75,7 @@ int nvdimm_init_nsarea(struct nvdimm_drvdata *ndd)
        memset(cmd, 0, sizeof(*cmd));
        nd_desc = nvdimm_bus->nd_desc;
        return nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
-                       ND_CMD_GET_CONFIG_SIZE, cmd, sizeof(*cmd));
+                       ND_CMD_GET_CONFIG_SIZE, cmd, sizeof(*cmd), NULL);
 }
 
 int nvdimm_init_config_data(struct nvdimm_drvdata *ndd)
@@ -120,7 +120,7 @@ int nvdimm_init_config_data(struct nvdimm_drvdata *ndd)
                cmd->in_offset = offset;
                rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
                                ND_CMD_GET_CONFIG_DATA, cmd,
-                               cmd->in_length + sizeof(*cmd));
+                               cmd->in_length + sizeof(*cmd), NULL);
                if (rc || cmd->status) {
                        rc = -ENXIO;
                        break;
@@ -171,7 +171,7 @@ int nvdimm_set_config_data(struct nvdimm_drvdata *ndd, size_t offset,
                status = ((void *) cmd) + cmd_size - sizeof(u32);
 
                rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
-                               ND_CMD_SET_CONFIG_DATA, cmd, cmd_size);
+                               ND_CMD_SET_CONFIG_DATA, cmd, cmd_size, NULL);
                if (rc || *status) {
                        rc = rc ? rc : -ENXIO;
                        break;

diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index 141ffdd..f398953 100644 (file)
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -48,7 +48,7 @@ struct nvdimm;
 struct nvdimm_bus_descriptor;
 typedef int (*ndctl_fn)(struct nvdimm_bus_descriptor *nd_desc,
                struct nvdimm *nvdimm, unsigned int cmd, void *buf,
-               unsigned int buf_len);
+               unsigned int buf_len, int *cmd_rc);
 
 struct nd_namespace_label;
 struct nvdimm_drvdata;

diff --git a/tools/testing/nvdimm/test/nfit.c b/tools/testing/nvdimm/test/nfit.c
index 27b808e..9ead779 100644 (file)
--- a/tools/testing/nvdimm/test/nfit.c
+++ b/tools/testing/nvdimm/test/nfit.c
@@ -261,7 +261,7 @@ static int nfit_test_cmd_ars_status(struct nd_cmd_ars_status *nd_cmd,
 
 static int nfit_test_ctl(struct nvdimm_bus_descriptor *nd_desc,
                struct nvdimm *nvdimm, unsigned int cmd, void *buf,
-               unsigned int buf_len)
+               unsigned int buf_len, int *cmd_rc)
 {
        struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc);
        struct nfit_test *t = container_of(acpi_desc, typeof(*t), acpi_desc);
@@ -315,6 +315,9 @@ static int nfit_test_ctl(struct nvdimm_bus_descriptor *nd_desc,
                }
        }
 
+       /* TODO: error status tests */
+       if (cmd_rc)
+               *cmd_rc = 0;
        return rc;
 }