- size_t map_size, dyn_size;
- unsigned int cpu;
- int i, j;
- ssize_t ret;
-
- if (!chosen) {
- size_t vm_size = VMALLOC_END - VMALLOC_START;
- size_t tot_size = nr_cpu_ids * PMD_SIZE;
-
- /* on non-NUMA, embedding is better */
- if (!pcpu_need_numa())
- return -EINVAL;
-
- /* don't consume more than 20% of vmalloc area */
- if (tot_size > vm_size / 5) {
- pr_info("PERCPU: too large chunk size %zuMB for "
- "large page remap\n", tot_size >> 20);
- return -EINVAL;
- }
- }
-
- /* need PSE */
- if (!cpu_has_pse) {
- pr_warning("PERCPU: lpage allocator requires PSE\n");
- return -EINVAL;
- }
-
- /*
- * Currently supports only single page. Supporting multiple
- * pages won't be too difficult if it ever becomes necessary.
- */
- pcpul_size = PFN_ALIGN(static_size + PERCPU_MODULE_RESERVE +
- PERCPU_DYNAMIC_RESERVE);
- if (pcpul_size > PMD_SIZE) {
- pr_warning("PERCPU: static data is larger than large page, "
- "can't use large page\n");
- return -EINVAL;
- }
- dyn_size = pcpul_size - static_size - PERCPU_FIRST_CHUNK_RESERVE;
-
- /* allocate pointer array and alloc large pages */
- map_size = PFN_ALIGN(nr_cpu_ids * sizeof(pcpul_map[0]));
- pcpul_map = alloc_bootmem(map_size);
-
- for_each_possible_cpu(cpu) {
- pcpul_map[cpu].cpu = cpu;
- pcpul_map[cpu].ptr = pcpu_alloc_bootmem(cpu, PMD_SIZE,
- PMD_SIZE);
- if (!pcpul_map[cpu].ptr) {
- pr_warning("PERCPU: failed to allocate large page "
- "for cpu%u\n", cpu);
- goto enomem;
- }
-
- /*
- * Only use pcpul_size bytes and give back the rest.
- *
- * Ingo: The 2MB up-rounding bootmem is needed to make
- * sure the partial 2MB page is still fully RAM - it's
- * not well-specified to have a PAT-incompatible area
- * (unmapped RAM, device memory, etc.) in that hole.
- */
- free_bootmem(__pa(pcpul_map[cpu].ptr + pcpul_size),
- PMD_SIZE - pcpul_size);
-
- memcpy(pcpul_map[cpu].ptr, __per_cpu_load, static_size);
- }
-
- /* allocate address and map */
- pcpul_vm.flags = VM_ALLOC;
- pcpul_vm.size = nr_cpu_ids * PMD_SIZE;
- vm_area_register_early(&pcpul_vm, PMD_SIZE);
-
- for_each_possible_cpu(cpu) {
- pmd_t *pmd, pmd_v;
-
- pmd = populate_extra_pmd((unsigned long)pcpul_vm.addr +
- cpu * PMD_SIZE);
- pmd_v = pfn_pmd(page_to_pfn(virt_to_page(pcpul_map[cpu].ptr)),
- PAGE_KERNEL_LARGE);
- set_pmd(pmd, pmd_v);
- }
-
- /* we're ready, commit */
- pr_info("PERCPU: Remapped at %p with large pages, static data "
- "%zu bytes\n", pcpul_vm.addr, static_size);
-
- ret = pcpu_setup_first_chunk(pcpul_get_page, static_size,
- PERCPU_FIRST_CHUNK_RESERVE, dyn_size,
- PMD_SIZE, pcpul_vm.addr, NULL);
-
- /* sort pcpul_map array for pcpu_lpage_remapped() */
- for (i = 0; i < nr_cpu_ids - 1; i++)
- for (j = i + 1; j < nr_cpu_ids; j++)
- if (pcpul_map[i].ptr > pcpul_map[j].ptr) {
- struct pcpul_ent tmp = pcpul_map[i];
- pcpul_map[i] = pcpul_map[j];
- pcpul_map[j] = tmp;
- }
-
- return ret;
-
-enomem:
- for_each_possible_cpu(cpu)
- if (pcpul_map[cpu].ptr)
- free_bootmem(__pa(pcpul_map[cpu].ptr), pcpul_size);
- free_bootmem(__pa(pcpul_map), map_size);
- return -ENOMEM;