/* Convert a region of vmalloc memory to an opal sg list */
struct opal_sg_list *opal_vmalloc_to_sg_list(void *vmalloc_addr,
unsigned long vmalloc_size)
{
struct opal_sg_list *sg, *first = NULL;
unsigned long i = 0;
sg = kzalloc(PAGE_SIZE, GFP_KERNEL);
if (!sg)
goto nomem;
first = sg;
while (vmalloc_size > 0) {
uint64_t data = vmalloc_to_pfn(vmalloc_addr) << PAGE_SHIFT;
uint64_t length = min(vmalloc_size, PAGE_SIZE);
sg->entry[i].data = cpu_to_be64(data);
sg->entry[i].length = cpu_to_be64(length);
i++;
if (i >= SG_ENTRIES_PER_NODE) {
struct opal_sg_list *next;
next = kzalloc(PAGE_SIZE, GFP_KERNEL);
if (!next)
goto nomem;
sg->length = cpu_to_be64(
i * sizeof(struct opal_sg_entry) + 16);
i = 0;
sg->next = cpu_to_be64(__pa(next));
sg = next;
}
vmalloc_addr += length;
vmalloc_size -= length;
}
sg->length = cpu_to_be64(i * sizeof(struct opal_sg_entry) + 16);
return first;
nomem:
pr_err("%s : Failed to allocate memory\n", __func__);
opal_free_sg_list(first);
return NULL;
}
static int64_t dump_read_data(struct dump_obj *dump)
{
struct opal_sg_list *list;
uint64_t addr;
int64_t rc;
/* Allocate memory */
dump->buffer = vzalloc(PAGE_ALIGN(dump->size));
if (!dump->buffer) {
pr_err("%s : Failed to allocate memory\n", __func__);
rc = -ENOMEM;
goto out;
}
/* Generate SG list */
list = opal_vmalloc_to_sg_list(dump->buffer, dump->size);
if (!list) {
rc = -ENOMEM;
goto out;
}
/* First entry address */
addr = __pa(list);
/* Fetch data */
rc = OPAL_BUSY_EVENT;
while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
rc = opal_dump_read(dump->id, addr);
if (rc == OPAL_BUSY_EVENT) {
opal_poll_events(NULL);
msleep(20);
}
}
if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL)
pr_warn("%s: Extract dump failed for ID 0x%x\n",
__func__, dump->id);
/* Free SG list */
opal_free_sg_list(list);
out:
return rc;
}
