libnvdimm: control (ioctl) messages for nvdimm_bus and nvdimm devices
Most discovery/configuration of the nvdimm-subsystem is done via sysfs
attributes. However, some nvdimm_bus instances, particularly the
ACPI.NFIT bus, define a small set of messages that can be passed to the
platform. For convenience we derive the initial libnvdimm-ioctl command
formats directly from the NFIT DSM Interface Example formats.
ND_CMD_SMART: media health and diagnostics
ND_CMD_GET_CONFIG_SIZE: size of the label space
ND_CMD_GET_CONFIG_DATA: read label space
ND_CMD_SET_CONFIG_DATA: write label space
ND_CMD_VENDOR: vendor-specific command passthrough
ND_CMD_ARS_CAP: report address-range-scrubbing capabilities
ND_CMD_ARS_START: initiate scrubbing
ND_CMD_ARS_STATUS: report on scrubbing state
ND_CMD_SMART_THRESHOLD: configure alarm thresholds for smart events
If a platform later defines different commands than this set it is
straightforward to extend support to those formats.
Most of the commands target a specific dimm. However, the
address-range-scrubbing commands target the bus. The 'commands'
attribute in sysfs of an nvdimm_bus, or nvdimm, enumerate the supported
commands for that object.
Cc: <linux-acpi@vger.kernel.org>
Cc: Robert Moore <robert.moore@intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reported-by: Nicholas Moulin <nicholas.w.moulin@linux.intel.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/nvdimm/bus.c b/drivers/nvdimm/bus.c
index a880257..15f3a3d 100644
--- a/drivers/nvdimm/bus.c
+++ b/drivers/nvdimm/bus.c
@@ -11,14 +11,18 @@
* General Public License for more details.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/vmalloc.h>
#include <linux/uaccess.h>
#include <linux/fcntl.h>
#include <linux/async.h>
+#include <linux/ndctl.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/io.h>
+#include <linux/mm.h>
#include "nd-core.h"
+int nvdimm_major;
static int nvdimm_bus_major;
static struct class *nd_class;
@@ -47,19 +51,325 @@
device_destroy(nd_class, MKDEV(nvdimm_bus_major, nvdimm_bus->id));
}
+static const struct nd_cmd_desc __nd_cmd_dimm_descs[] = {
+ [ND_CMD_IMPLEMENTED] = { },
+ [ND_CMD_SMART] = {
+ .out_num = 2,
+ .out_sizes = { 4, 8, },
+ },
+ [ND_CMD_SMART_THRESHOLD] = {
+ .out_num = 2,
+ .out_sizes = { 4, 8, },
+ },
+ [ND_CMD_DIMM_FLAGS] = {
+ .out_num = 2,
+ .out_sizes = { 4, 4 },
+ },
+ [ND_CMD_GET_CONFIG_SIZE] = {
+ .out_num = 3,
+ .out_sizes = { 4, 4, 4, },
+ },
+ [ND_CMD_GET_CONFIG_DATA] = {
+ .in_num = 2,
+ .in_sizes = { 4, 4, },
+ .out_num = 2,
+ .out_sizes = { 4, UINT_MAX, },
+ },
+ [ND_CMD_SET_CONFIG_DATA] = {
+ .in_num = 3,
+ .in_sizes = { 4, 4, UINT_MAX, },
+ .out_num = 1,
+ .out_sizes = { 4, },
+ },
+ [ND_CMD_VENDOR] = {
+ .in_num = 3,
+ .in_sizes = { 4, 4, UINT_MAX, },
+ .out_num = 3,
+ .out_sizes = { 4, 4, UINT_MAX, },
+ },
+};
+
+const struct nd_cmd_desc *nd_cmd_dimm_desc(int cmd)
+{
+ if (cmd < ARRAY_SIZE(__nd_cmd_dimm_descs))
+ return &__nd_cmd_dimm_descs[cmd];
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(nd_cmd_dimm_desc);
+
+static const struct nd_cmd_desc __nd_cmd_bus_descs[] = {
+ [ND_CMD_IMPLEMENTED] = { },
+ [ND_CMD_ARS_CAP] = {
+ .in_num = 2,
+ .in_sizes = { 8, 8, },
+ .out_num = 2,
+ .out_sizes = { 4, 4, },
+ },
+ [ND_CMD_ARS_START] = {
+ .in_num = 4,
+ .in_sizes = { 8, 8, 2, 6, },
+ .out_num = 1,
+ .out_sizes = { 4, },
+ },
+ [ND_CMD_ARS_STATUS] = {
+ .out_num = 2,
+ .out_sizes = { 4, UINT_MAX, },
+ },
+};
+
+const struct nd_cmd_desc *nd_cmd_bus_desc(int cmd)
+{
+ if (cmd < ARRAY_SIZE(__nd_cmd_bus_descs))
+ return &__nd_cmd_bus_descs[cmd];
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(nd_cmd_bus_desc);
+
+u32 nd_cmd_in_size(struct nvdimm *nvdimm, int cmd,
+ const struct nd_cmd_desc *desc, int idx, void *buf)
+{
+ if (idx >= desc->in_num)
+ return UINT_MAX;
+
+ if (desc->in_sizes[idx] < UINT_MAX)
+ return desc->in_sizes[idx];
+
+ if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA && idx == 2) {
+ struct nd_cmd_set_config_hdr *hdr = buf;
+
+ return hdr->in_length;
+ } else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2) {
+ struct nd_cmd_vendor_hdr *hdr = buf;
+
+ return hdr->in_length;
+ }
+
+ return UINT_MAX;
+}
+EXPORT_SYMBOL_GPL(nd_cmd_in_size);
+
+u32 nd_cmd_out_size(struct nvdimm *nvdimm, int cmd,
+ const struct nd_cmd_desc *desc, int idx, const u32 *in_field,
+ const u32 *out_field)
+{
+ if (idx >= desc->out_num)
+ return UINT_MAX;
+
+ if (desc->out_sizes[idx] < UINT_MAX)
+ return desc->out_sizes[idx];
+
+ if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && idx == 1)
+ return in_field[1];
+ else if (nvdimm && cmd == ND_CMD_VENDOR && idx == 2)
+ return out_field[1];
+ else if (!nvdimm && cmd == ND_CMD_ARS_STATUS && idx == 1)
+ return ND_CMD_ARS_STATUS_MAX;
+
+ return UINT_MAX;
+}
+EXPORT_SYMBOL_GPL(nd_cmd_out_size);
+
+static int __nd_ioctl(struct nvdimm_bus *nvdimm_bus, struct nvdimm *nvdimm,
+ int read_only, unsigned int ioctl_cmd, unsigned long arg)
+{
+ struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
+ size_t buf_len = 0, in_len = 0, out_len = 0;
+ static char out_env[ND_CMD_MAX_ENVELOPE];
+ static char in_env[ND_CMD_MAX_ENVELOPE];
+ const struct nd_cmd_desc *desc = NULL;
+ unsigned int cmd = _IOC_NR(ioctl_cmd);
+ void __user *p = (void __user *) arg;
+ struct device *dev = &nvdimm_bus->dev;
+ const char *cmd_name, *dimm_name;
+ unsigned long dsm_mask;
+ void *buf;
+ int rc, i;
+
+ if (nvdimm) {
+ desc = nd_cmd_dimm_desc(cmd);
+ cmd_name = nvdimm_cmd_name(cmd);
+ dsm_mask = nvdimm->dsm_mask ? *(nvdimm->dsm_mask) : 0;
+ dimm_name = dev_name(&nvdimm->dev);
+ } else {
+ desc = nd_cmd_bus_desc(cmd);
+ cmd_name = nvdimm_bus_cmd_name(cmd);
+ dsm_mask = nd_desc->dsm_mask;
+ dimm_name = "bus";
+ }
+
+ if (!desc || (desc->out_num + desc->in_num == 0) ||
+ !test_bit(cmd, &dsm_mask))
+ return -ENOTTY;
+
+ /* fail write commands (when read-only) */
+ if (read_only)
+ switch (ioctl_cmd) {
+ case ND_IOCTL_VENDOR:
+ case ND_IOCTL_SET_CONFIG_DATA:
+ case ND_IOCTL_ARS_START:
+ dev_dbg(&nvdimm_bus->dev, "'%s' command while read-only.\n",
+ nvdimm ? nvdimm_cmd_name(cmd)
+ : nvdimm_bus_cmd_name(cmd));
+ return -EPERM;
+ default:
+ break;
+ }
+
+ /* process an input envelope */
+ for (i = 0; i < desc->in_num; i++) {
+ u32 in_size, copy;
+
+ in_size = nd_cmd_in_size(nvdimm, cmd, desc, i, in_env);
+ if (in_size == UINT_MAX) {
+ dev_err(dev, "%s:%s unknown input size cmd: %s field: %d\n",
+ __func__, dimm_name, cmd_name, i);
+ return -ENXIO;
+ }
+ if (!access_ok(VERIFY_READ, p + in_len, in_size))
+ return -EFAULT;
+ if (in_len < sizeof(in_env))
+ copy = min_t(u32, sizeof(in_env) - in_len, in_size);
+ else
+ copy = 0;
+ if (copy && copy_from_user(&in_env[in_len], p + in_len, copy))
+ return -EFAULT;
+ in_len += in_size;
+ }
+
+ /* process an output envelope */
+ for (i = 0; i < desc->out_num; i++) {
+ u32 out_size = nd_cmd_out_size(nvdimm, cmd, desc, i,
+ (u32 *) in_env, (u32 *) out_env);
+ u32 copy;
+
+ if (out_size == UINT_MAX) {
+ dev_dbg(dev, "%s:%s unknown output size cmd: %s field: %d\n",
+ __func__, dimm_name, cmd_name, i);
+ return -EFAULT;
+ }
+ if (!access_ok(VERIFY_WRITE, p + in_len + out_len, out_size))
+ return -EFAULT;
+ if (out_len < sizeof(out_env))
+ copy = min_t(u32, sizeof(out_env) - out_len, out_size);
+ else
+ copy = 0;
+ if (copy && copy_from_user(&out_env[out_len],
+ p + in_len + out_len, copy))
+ return -EFAULT;
+ out_len += out_size;
+ }
+
+ buf_len = out_len + in_len;
+ if (!access_ok(VERIFY_WRITE, p, sizeof(buf_len)))
+ return -EFAULT;
+
+ if (buf_len > ND_IOCTL_MAX_BUFLEN) {
+ dev_dbg(dev, "%s:%s cmd: %s buf_len: %zu > %d\n", __func__,
+ dimm_name, cmd_name, buf_len,
+ ND_IOCTL_MAX_BUFLEN);
+ return -EINVAL;
+ }
+
+ buf = vmalloc(buf_len);
+ if (!buf)
+ return -ENOMEM;
+
+ if (copy_from_user(buf, p, buf_len)) {
+ rc = -EFAULT;
+ goto out;
+ }
+
+ rc = nd_desc->ndctl(nd_desc, nvdimm, cmd, buf, buf_len);
+ if (rc < 0)
+ goto out;
+ if (copy_to_user(p, buf, buf_len))
+ rc = -EFAULT;
+ out:
+ vfree(buf);
+ return rc;
+}
+
static long nd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
- return -ENXIO;
+ long id = (long) file->private_data;
+ int rc = -ENXIO, read_only;
+ struct nvdimm_bus *nvdimm_bus;
+
+ read_only = (O_RDWR != (file->f_flags & O_ACCMODE));
+ mutex_lock(&nvdimm_bus_list_mutex);
+ list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
+ if (nvdimm_bus->id == id) {
+ rc = __nd_ioctl(nvdimm_bus, NULL, read_only, cmd, arg);
+ break;
+ }
+ }
+ mutex_unlock(&nvdimm_bus_list_mutex);
+
+ return rc;
+}
+
+static int match_dimm(struct device *dev, void *data)
+{
+ long id = (long) data;
+
+ if (is_nvdimm(dev)) {
+ struct nvdimm *nvdimm = to_nvdimm(dev);
+
+ return nvdimm->id == id;
+ }
+
+ return 0;
+}
+
+static long nvdimm_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ int rc = -ENXIO, read_only;
+ struct nvdimm_bus *nvdimm_bus;
+
+ read_only = (O_RDWR != (file->f_flags & O_ACCMODE));
+ mutex_lock(&nvdimm_bus_list_mutex);
+ list_for_each_entry(nvdimm_bus, &nvdimm_bus_list, list) {
+ struct device *dev = device_find_child(&nvdimm_bus->dev,
+ file->private_data, match_dimm);
+ struct nvdimm *nvdimm;
+
+ if (!dev)
+ continue;
+
+ nvdimm = to_nvdimm(dev);
+ rc = __nd_ioctl(nvdimm_bus, nvdimm, read_only, cmd, arg);
+ put_device(dev);
+ break;
+ }
+ mutex_unlock(&nvdimm_bus_list_mutex);
+
+ return rc;
+}
+
+static int nd_open(struct inode *inode, struct file *file)
+{
+ long minor = iminor(inode);
+
+ file->private_data = (void *) minor;
+ return 0;
}
static const struct file_operations nvdimm_bus_fops = {
.owner = THIS_MODULE,
- .open = nonseekable_open,
+ .open = nd_open,
.unlocked_ioctl = nd_ioctl,
.compat_ioctl = nd_ioctl,
.llseek = noop_llseek,
};
+static const struct file_operations nvdimm_fops = {
+ .owner = THIS_MODULE,
+ .open = nd_open,
+ .unlocked_ioctl = nvdimm_ioctl,
+ .compat_ioctl = nvdimm_ioctl,
+ .llseek = noop_llseek,
+};
+
int __init nvdimm_bus_init(void)
{
int rc;
@@ -70,9 +380,14 @@
rc = register_chrdev(0, "ndctl", &nvdimm_bus_fops);
if (rc < 0)
- goto err_chrdev;
+ goto err_bus_chrdev;
nvdimm_bus_major = rc;
+ rc = register_chrdev(0, "dimmctl", &nvdimm_fops);
+ if (rc < 0)
+ goto err_dimm_chrdev;
+ nvdimm_major = rc;
+
nd_class = class_create(THIS_MODULE, "nd");
if (IS_ERR(nd_class))
goto err_class;
@@ -80,8 +395,10 @@
return 0;
err_class:
+ unregister_chrdev(nvdimm_major, "dimmctl");
+ err_dimm_chrdev:
unregister_chrdev(nvdimm_bus_major, "ndctl");
- err_chrdev:
+ err_bus_chrdev:
bus_unregister(&nvdimm_bus_type);
return rc;
@@ -91,5 +408,6 @@
{
class_destroy(nd_class);
unregister_chrdev(nvdimm_bus_major, "ndctl");
+ unregister_chrdev(nvdimm_major, "dimmctl");
bus_unregister(&nvdimm_bus_type);
}