"Pratik R. Sampat" <psampat@xxxxxxxxxxxxx> writes:
> +#include <linux/module.h>
> +#include <linux/types.h>
> +#include <linux/errno.h>
> +#include <linux/init.h>
> +#include <linux/seq_file.h>
> +#include <linux/slab.h>
> +#include <linux/uaccess.h>
> +#include <linux/hugetlb.h>
> +#include <asm/lppaca.h>
> +#include <asm/hvcall.h>
> +#include <asm/firmware.h>
> +#include <asm/time.h>
> +#include <asm/prom.h>
> +#include <asm/vdso_datapage.h>
> +#include <asm/vio.h>
> +#include <asm/mmu.h>
> +#include <asm/machdep.h>
> +#include <asm/drmem.h>
Do you need all of these headers? Sorry to mention just now, I seem to have
dropped this comment from a previous review.
> +
> +#include "pseries.h"
> +
> +/*
> + * Flag attributes to fetch either all or one attribute from the HCALL
> + * flag = BE(0) => fetch all attributes with firstAttributeId = 0
> + * flag = BE(1) => fetch a single attribute with firstAttributeId = id
> + */
> +#define ESI_FLAGS_ALL 0
> +#define ESI_FLAGS_SINGLE PPC_BIT(0)
> +
> +#define MAX_ATTRS 3
> +
> +struct papr_attr {
> + u64 id;
> + struct kobj_attribute kobj_attr;
> +};
> +struct papr_group {
> + struct attribute_group pg;
> + struct papr_attr pgattrs[MAX_ATTRS];
> +} *pgs;
> +
> +/* /sys/firmware/papr */
> +struct kobject *papr_kobj;
> +/* /sys/firmware/papr/energy_scale_info */
> +struct kobject *esi_kobj;
> +
> +/*
> + * Extract and export the description of the energy scale attribute
> + *
Extra line here.
> + */
> +static ssize_t papr_show_desc(struct kobject *kobj,
> + struct kobj_attribute *kobj_attr,
> + char *buf)
> +{
> + struct papr_attr *pattr = container_of(kobj_attr, struct papr_attr,
> + kobj_attr);
> + struct h_energy_scale_info_hdr *t_hdr;
> + struct energy_scale_attribute *t_esi;
> + char *t_buf;
> + int ret = 0;
> +
> + t_buf = kmalloc(MAX_BUF_SZ, GFP_KERNEL);
> + if (t_buf == NULL)
> + return -ENOMEM;
> +
> + ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, ESI_FLAGS_SINGLE,
> + pattr->id, virt_to_phys(t_buf),
> + MAX_BUF_SZ);
> +
> + if (ret != H_SUCCESS) {
> + pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO");
> + goto out;
> + }
> +
> + t_hdr = (struct h_energy_scale_info_hdr *) t_buf;
> + t_esi = (struct energy_scale_attribute *)
> + (t_buf + be64_to_cpu(t_hdr->array_offset));
> +
> + ret = snprintf(buf, sizeof(t_esi->desc), "%s\n", t_esi->desc);
> + if (ret < 0)
> + ret = -EIO;
> +out:
> + kfree(t_buf);
> +
> + return ret;
> +}
> +
> +/*
> + * Extract and export the numeric value of the energy scale attributes
> + */
> +static ssize_t papr_show_value(struct kobject *kobj,
> + struct kobj_attribute *kobj_attr,
> + char *buf)
> +{
> + struct papr_attr *pattr = container_of(kobj_attr, struct papr_attr,
> + kobj_attr);
> + struct h_energy_scale_info_hdr *t_hdr;
> + struct energy_scale_attribute *t_esi;
> + char *t_buf;
> + int ret = 0;
> +
> + t_buf = kmalloc(MAX_BUF_SZ, GFP_KERNEL);
> + if (t_buf == NULL)
> + return -ENOMEM;
> +
> + ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, ESI_FLAGS_SINGLE,
> + pattr->id, virt_to_phys(t_buf),
> + MAX_BUF_SZ);
> +
> + if (ret != H_SUCCESS) {
> + pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO");
> + goto out;
> + }
> +
> + t_hdr = (struct h_energy_scale_info_hdr *) t_buf;
> + t_esi = (struct energy_scale_attribute *)
> + (t_buf + be64_to_cpu(t_hdr->array_offset));
> +
> + ret = snprintf(buf, sizeof(t_esi->value), "%llu\n",
> + be64_to_cpu(t_esi->value));
> + if (ret < 0)
> + ret = -EIO;
> +out:
> + kfree(t_buf);
> +
> + return ret;
> +}
> +
> +/*
> + * Extract and export the value description in string format of the energy
> + * scale attributes
> + */
> +static ssize_t papr_show_value_desc(struct kobject *kobj,
> + struct kobj_attribute *kobj_attr,
> + char *buf)
> +{
> + struct papr_attr *pattr = container_of(kobj_attr, struct papr_attr,
> + kobj_attr);
> + struct h_energy_scale_info_hdr *t_hdr;
> + struct energy_scale_attribute *t_esi;
> + char *t_buf;
> + int ret = 0;
> +
> + t_buf = kmalloc(MAX_BUF_SZ, GFP_KERNEL);
> + if (t_buf == NULL)
> + return -ENOMEM;
> +
> + ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, ESI_FLAGS_SINGLE,
> + pattr->id, virt_to_phys(t_buf),
> + MAX_BUF_SZ);
> +
> + if (ret != H_SUCCESS) {
> + pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO");
> + goto out;
> + }
> +
> + t_hdr = (struct h_energy_scale_info_hdr *) t_buf;
> + t_esi = (struct energy_scale_attribute *)
> + (t_buf + be64_to_cpu(t_hdr->array_offset));
> +
> + ret = snprintf(buf, sizeof(t_esi->value_desc), "%s\n",
> + t_esi->value_desc);
> + if (ret < 0)
> + ret = -EIO;
> +out:
> + kfree(t_buf);
> +
> + return ret;
> +}
> +
> +static struct papr_ops_info {
> + const char *attr_name;
> + ssize_t (*show)(struct kobject *kobj, struct kobj_attribute *kobj_attr,
> + char *buf);
> +} ops_info[MAX_ATTRS] = {
> + { "desc", papr_show_desc },
> + { "value", papr_show_value },
> + { "value_desc", papr_show_value_desc },
> +};
> +
> +static void add_attr(u64 id, int index, struct papr_attr *attr)
> +{
> + attr->id = id;
> + sysfs_attr_init(&attr->kobj_attr.attr);
> + attr->kobj_attr.attr.name = ops_info[index].attr_name;
> + attr->kobj_attr.attr.mode = 0444;
> + attr->kobj_attr.show = ops_info[index].show;
> +}
> +
> +static int add_attr_group(u64 id, int len, struct papr_group *pg,
> + bool show_val_desc)
> +{
> + int i;
> +
> + for (i = 0; i < len; i++) {
Could use MAX_ATTRS directly.
> + if (!strcmp(ops_info[i].attr_name, "value_desc") &&
> + !show_val_desc) {
> + continue;
> + }
> + add_attr(id, i, &pg->pgattrs[i]);
> + pg->pg.attrs[i] = &pg->pgattrs[i].kobj_attr.attr;
> + }
> +
> + return sysfs_create_group(esi_kobj, &pg->pg);
> +}
> +
> +static int __init papr_init(void)
> +{
> + struct h_energy_scale_info_hdr *esi_hdr;
> + struct energy_scale_attribute *esi_attrs;
> + uint64_t num_attrs;
> + int ret, idx, i;
> + char *esi_buf;
> +
> + if (!firmware_has_feature(FW_FEATURE_LPAR))
> + return -ENXIO;
> +
> + esi_buf = kmalloc(MAX_BUF_SZ, GFP_KERNEL);
> + if (esi_buf == NULL)
> + return -ENOMEM;
> + /*
> + * hcall(
> + * uint64 H_GET_ENERGY_SCALE_INFO, // Get energy scale info
> + * uint64 flags, // Per the flag request
> + * uint64 firstAttributeId, // The attribute id
> + * uint64 bufferAddress, // Guest physical address of the output buffer
> + * uint64 bufferSize); // The size in bytes of the output buffer
> + */
> + ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, ESI_FLAGS_ALL, 0,
> + virt_to_phys(esi_buf), MAX_BUF_SZ);
> + if (ret != H_SUCCESS) {
> + pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO");
> + goto out;
> + }
> +
> + esi_hdr = (struct h_energy_scale_info_hdr *) esi_buf;
> + if (esi_hdr->data_header_version != ESI_VERSION) {
> + pr_warn("H_GET_ENERGY_SCALE_INFO VER MISMATCH - EXP: 0x%x, REC: 0x%x",
> + ESI_VERSION, esi_hdr->data_header_version);
> + }
> +
> + num_attrs = be64_to_cpu(esi_hdr->num_attrs);
> + esi_attrs = (struct energy_scale_attribute *)
> + (esi_buf + be64_to_cpu(esi_hdr->array_offset));
> +
> + pgs = kcalloc(num_attrs, sizeof(*pgs), GFP_KERNEL);
> + if (!pgs)
> + goto out;
> +
> + papr_kobj = kobject_create_and_add("papr", firmware_kobj);
> + if (!papr_kobj) {
> + pr_warn("kobject_create_and_add papr failed\n");
> + goto out_pgs;
> + }
> +
> + esi_kobj = kobject_create_and_add("energy_scale_info", papr_kobj);
> + if (!esi_kobj) {
> + pr_warn("kobject_create_and_add energy_scale_info failed\n");
> + goto out_kobj;
> + }
> +
> + for (idx = 0; idx < num_attrs; idx++) {
> + bool show_val_desc = true;
> +
> + pgs[idx].pg.attrs = kcalloc(MAX_ATTRS + 1,
> + sizeof(*pgs[idx].pg.attrs),
> + GFP_KERNEL);
> + if (!pgs[idx].pg.attrs)
> + goto out_ekobj;
What about the attrs allocated during the previous iterations?
> +
> + pgs[idx].pg.name = kasprintf(GFP_KERNEL, "%lld",
> + be64_to_cpu(esi_attrs[idx].id));
> + if (pgs[idx].pg.name == NULL) {
> + for (i = idx; i >= 0; i--)
> + kfree(pgs[i].pg.attrs);
> + goto out_ekobj;
> + }
> + /* Do not add the value description if it does not exist */
> + if (strlen(esi_attrs[idx].value_desc) == 0)
strnlen
> + show_val_desc = false;
> +
> + if (add_attr_group(be64_to_cpu(esi_attrs[idx].id),
> + MAX_ATTRS, &pgs[idx], show_val_desc)) {
> + pr_warn("Failed to create papr attribute group %s\n",
> + pgs[idx].pg.name);
> + goto out_pgattrs;
> + }
> + }
> +
> + kfree(esi_buf);
> + return 0;
> +
> +out_pgattrs:
> + for (i = 0; i < MAX_ATTRS ; i++) {
pgs is num_attrs long
> + kfree(pgs[i].pg.attrs);
> + kfree(pgs[i].pg.name);
> + }
> +out_ekobj:
> + kobject_put(esi_kobj);
> +out_kobj:
> + kobject_put(papr_kobj);
> +out_pgs:
> + kfree(pgs);
> +out:
> + kfree(esi_buf);
> +
> + return -ENOMEM;
> +}
> +
> +machine_device_initcall(pseries, papr_init);
