/**
* cmm_free_pages - Free pages and mark them as active
* @nr: number of pages to free
*
* Return value:
* number of pages requested to be freed which were not
**/
static long cmm_free_pages(long nr)
{
struct cmm_page_array *pa;
unsigned long addr;
cmm_dbg("Begin free of %ld pages.\n", nr);
spin_lock(&cmm_lock);
pa = cmm_page_list;
while (nr) {
if (!pa || pa->index <= 0)
break;
addr = pa->page[--pa->index];
if (pa->index == 0) {
pa = pa->next;
free_page((unsigned long) cmm_page_list);
cmm_page_list = pa;
}
plpar_page_set_active(__pa(addr));
free_page(addr);
loaned_pages--;
nr--;
totalram_pages++;
}
spin_unlock(&cmm_lock);
cmm_dbg("End request with %ld pages unfulfilled\n", nr);
return nr;
}
/**
* cmm_mem_going_offline - Unloan pages where memory is to be removed
* @arg: memory_notify structure with page range to be offlined
*
* Return value:
* 0 on success
**/
static int cmm_mem_going_offline(void *arg)
{
struct memory_notify *marg = arg;
unsigned long start_page = (unsigned long)pfn_to_kaddr(marg->start_pfn);
unsigned long end_page = start_page + (marg->nr_pages << PAGE_SHIFT);
struct cmm_page_array *pa_curr, *pa_last, *npa;
unsigned long idx;
unsigned long freed = 0;
cmm_dbg("Memory going offline, searching 0x%lx (%ld pages).\n",
start_page, marg->nr_pages);
spin_lock(&cmm_lock);
/* Search the page list for pages in the range to be offlined */
pa_last = pa_curr = cmm_page_list;
while (pa_curr) {
for (idx = (pa_curr->index - 1); (idx + 1) > 0; idx--) {
if ((pa_curr->page[idx] < start_page) ||
(pa_curr->page[idx] >= end_page))
continue;
plpar_page_set_active(__pa(pa_curr->page[idx]));
free_page(pa_curr->page[idx]);
freed++;
loaned_pages--;
totalram_pages++;
pa_curr->page[idx] = pa_last->page[--pa_last->index];
if (pa_last->index == 0) {
if (pa_curr == pa_last)
pa_curr = pa_last->next;
pa_last = pa_last->next;
free_page((unsigned long)cmm_page_list);
cmm_page_list = pa_last;
continue;
}
}
pa_curr = pa_curr->next;
}
/* Search for page list structures in the range to be offlined */
pa_last = NULL;
pa_curr = cmm_page_list;
while (pa_curr) {
if (((unsigned long)pa_curr >= start_page) &&
((unsigned long)pa_curr < end_page)) {
npa = (struct cmm_page_array *)__get_free_page(
GFP_NOIO | __GFP_NOWARN |
__GFP_NORETRY | __GFP_NOMEMALLOC);
if (!npa) {
spin_unlock(&cmm_lock);
cmm_dbg("Failed to allocate memory for list "
"management. Memory hotplug "
"failed.\n");
return ENOMEM;
}
memcpy(npa, pa_curr, PAGE_SIZE);
if (pa_curr == cmm_page_list)
cmm_page_list = npa;
if (pa_last)
pa_last->next = npa;
free_page((unsigned long) pa_curr);
freed++;
pa_curr = npa;
}
pa_last = pa_curr;
pa_curr = pa_curr->next;
}
spin_unlock(&cmm_lock);
cmm_dbg("Released %ld pages in the search range.\n", freed);
return 0;
}
