+/*
+ * Channel measurement related functions
+ */
+static ssize_t
+chp_measurement_chars_read(struct kobject *kobj, char *buf, loff_t off,
+ size_t count)
+{
+ struct channel_path *chp;
+ unsigned int size;
+
+ chp = to_channelpath(container_of(kobj, struct device, kobj));
+ if (!chp->cmg_chars)
+ return 0;
+
+ size = sizeof(struct cmg_chars);
+
+ if (off > size)
+ return 0;
+ if (off + count > size)
+ count = size - off;
+ memcpy(buf, chp->cmg_chars + off, count);
+ return count;
+}
+
+static struct bin_attribute chp_measurement_chars_attr = {
+ .attr = {
+ .name = "measurement_chars",
+ .mode = S_IRUSR,
+ .owner = THIS_MODULE,
+ },
+ .size = sizeof(struct cmg_chars),
+ .read = chp_measurement_chars_read,
+};
+
+static void
+chp_measurement_copy_block(struct cmg_entry *buf,
+ struct channel_subsystem *css, int chpid)
+{
+ void *area;
+ struct cmg_entry *entry, reference_buf;
+ int idx;
+
+ if (chpid < 128) {
+ area = css->cub_addr1;
+ idx = chpid;
+ } else {
+ area = css->cub_addr2;
+ idx = chpid - 128;
+ }
+ entry = area + (idx * sizeof(struct cmg_entry));
+ do {
+ memcpy(buf, entry, sizeof(*entry));
+ memcpy(&reference_buf, entry, sizeof(*entry));
+ } while (reference_buf.values[0] != buf->values[0]);
+}
+
+static ssize_t
+chp_measurement_read(struct kobject *kobj, char *buf, loff_t off, size_t count)
+{
+ struct channel_path *chp;
+ struct channel_subsystem *css;
+ unsigned int size;
+
+ chp = to_channelpath(container_of(kobj, struct device, kobj));
+ css = to_css(chp->dev.parent);
+
+ size = sizeof(struct cmg_entry);
+
+ /* Only allow single reads. */
+ if (off || count < size)
+ return 0;
+ chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->id);
+ count = size;
+ return count;
+}
+
+static struct bin_attribute chp_measurement_attr = {
+ .attr = {
+ .name = "measurement",
+ .mode = S_IRUSR,
+ .owner = THIS_MODULE,
+ },
+ .size = sizeof(struct cmg_entry),
+ .read = chp_measurement_read,
+};
+
+static void
+chsc_remove_chp_cmg_attr(struct channel_path *chp)
+{
+ sysfs_remove_bin_file(&chp->dev.kobj, &chp_measurement_chars_attr);
+ sysfs_remove_bin_file(&chp->dev.kobj, &chp_measurement_attr);
+}
+
+static int
+chsc_add_chp_cmg_attr(struct channel_path *chp)
+{
+ int ret;
+
+ ret = sysfs_create_bin_file(&chp->dev.kobj,
+ &chp_measurement_chars_attr);
+ if (ret)
+ return ret;
+ ret = sysfs_create_bin_file(&chp->dev.kobj, &chp_measurement_attr);
+ if (ret)
+ sysfs_remove_bin_file(&chp->dev.kobj,
+ &chp_measurement_chars_attr);
+ return ret;
+}
+
+static void
+chsc_remove_cmg_attr(struct channel_subsystem *css)
+{
+ int i;
+
+ for (i = 0; i <= __MAX_CHPID; i++) {
+ if (!css->chps[i])
+ continue;
+ chsc_remove_chp_cmg_attr(css->chps[i]);
+ }
+}
+
+static int
+chsc_add_cmg_attr(struct channel_subsystem *css)
+{
+ int i, ret;
+
+ ret = 0;
+ for (i = 0; i <= __MAX_CHPID; i++) {
+ if (!css->chps[i])
+ continue;
+ ret = chsc_add_chp_cmg_attr(css->chps[i]);
+ if (ret)
+ goto cleanup;
+ }
+ return ret;
+cleanup:
+ for (--i; i >= 0; i--) {
+ if (!css->chps[i])
+ continue;
+ chsc_remove_chp_cmg_attr(css->chps[i]);
+ }
+ return ret;
+}
+
+
+static int
+__chsc_do_secm(struct channel_subsystem *css, int enable, void *page)
+{
+ struct {
+ struct chsc_header request;
+ u32 operation_code : 2;
+ u32 : 30;
+ u32 key : 4;
+ u32 : 28;
+ u32 zeroes1;
+ u32 cub_addr1;
+ u32 zeroes2;
+ u32 cub_addr2;
+ u32 reserved[13];
+ struct chsc_header response;
+ u32 status : 8;
+ u32 : 4;
+ u32 fmt : 4;
+ u32 : 16;
+ } *secm_area;
+ int ret, ccode;
+
+ secm_area = page;
+ secm_area->request.length = 0x0050;
+ secm_area->request.code = 0x0016;
+
+ secm_area->key = PAGE_DEFAULT_KEY;
+ secm_area->cub_addr1 = (u64)(unsigned long)css->cub_addr1;
+ secm_area->cub_addr2 = (u64)(unsigned long)css->cub_addr2;
+
+ secm_area->operation_code = enable ? 0 : 1;
+
+ ccode = chsc(secm_area);
+ if (ccode > 0)
+ return (ccode == 3) ? -ENODEV : -EBUSY;
+
+ switch (secm_area->response.code) {
+ case 0x0001: /* Success. */
+ ret = 0;
+ break;
+ case 0x0003: /* Invalid block. */
+ case 0x0007: /* Invalid format. */
+ case 0x0008: /* Other invalid block. */
+ CIO_CRW_EVENT(2, "Error in chsc request block!\n");
+ ret = -EINVAL;
+ break;
+ case 0x0004: /* Command not provided in model. */
+ CIO_CRW_EVENT(2, "Model does not provide secm\n");
+ ret = -EOPNOTSUPP;
+ break;
+ case 0x0102: /* cub adresses incorrect */
+ CIO_CRW_EVENT(2, "Invalid addresses in chsc request block\n");
+ ret = -EINVAL;
+ break;
+ case 0x0103: /* key error */
+ CIO_CRW_EVENT(2, "Access key error in secm\n");
+ ret = -EINVAL;
+ break;
+ case 0x0105: /* error while starting */
+ CIO_CRW_EVENT(2, "Error while starting channel measurement\n");
+ ret = -EIO;
+ break;
+ default:
+ CIO_CRW_EVENT(2, "Unknown CHSC response %d\n",
+ secm_area->response.code);
+ ret = -EIO;
+ }
+ return ret;
+}
+
+int
+chsc_secm(struct channel_subsystem *css, int enable)
+{
+ void *secm_area;
+ int ret;
+
+ secm_area = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+ if (!secm_area)
+ return -ENOMEM;
+
+ mutex_lock(&css->mutex);
+ if (enable && !css->cm_enabled) {
+ css->cub_addr1 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+ css->cub_addr2 = (void *)get_zeroed_page(GFP_KERNEL | GFP_DMA);
+ if (!css->cub_addr1 || !css->cub_addr2) {
+ free_page((unsigned long)css->cub_addr1);
+ free_page((unsigned long)css->cub_addr2);
+ free_page((unsigned long)secm_area);
+ mutex_unlock(&css->mutex);
+ return -ENOMEM;
+ }
+ }
+ ret = __chsc_do_secm(css, enable, secm_area);
+ if (!ret) {
+ css->cm_enabled = enable;
+ if (css->cm_enabled) {
+ ret = chsc_add_cmg_attr(css);
+ if (ret) {
+ memset(secm_area, 0, PAGE_SIZE);
+ __chsc_do_secm(css, 0, secm_area);
+ css->cm_enabled = 0;
+ }
+ } else
+ chsc_remove_cmg_attr(css);
+ }
+ if (enable && !css->cm_enabled) {
+ free_page((unsigned long)css->cub_addr1);
+ free_page((unsigned long)css->cub_addr2);
+ }
+ mutex_unlock(&css->mutex);
+ free_page((unsigned long)secm_area);
+ return ret;
+}
+