| 1 | // SPDX-License-Identifier: GPL-2.0 |
|---|
| 2 | |
|---|
| 3 | #include <linux/pgtable.h> |
|---|
| 4 | #include <asm/abs_lowcore.h> |
|---|
| 5 | |
|---|
| 6 | unsigned long __bootdata_preserved(__abs_lowcore); |
|---|
| 7 | |
|---|
| 8 | int abs_lowcore_map(int cpu, struct lowcore *lc, bool alloc) |
|---|
| 9 | { |
|---|
| 10 | unsigned long addr = __abs_lowcore + (cpu * sizeof(struct lowcore)); |
|---|
| 11 | unsigned long phys = __pa(lc); |
|---|
| 12 | int rc, i; |
|---|
| 13 | |
|---|
| 14 | for (i = 0; i < LC_PAGES; i++) { |
|---|
| 15 | rc = __vmem_map_4k_page(addr, phys, PAGE_KERNEL, alloc); |
|---|
| 16 | if (rc) { |
|---|
| 17 | /* |
|---|
| 18 | * Do not unmap allocated page tables in case the |
|---|
| 19 | * allocation was not requested. In such a case the |
|---|
| 20 | * request is expected coming from an atomic context, |
|---|
| 21 | * while the unmap attempt might sleep. |
|---|
| 22 | */ |
|---|
| 23 | if (alloc) { |
|---|
| 24 | for (--i; i >= 0; i--) { |
|---|
| 25 | addr -= PAGE_SIZE; |
|---|
| 26 | vmem_unmap_4k_page(addr); |
|---|
| 27 | } |
|---|
| 28 | } |
|---|
| 29 | return rc; |
|---|
| 30 | } |
|---|
| 31 | addr += PAGE_SIZE; |
|---|
| 32 | phys += PAGE_SIZE; |
|---|
| 33 | } |
|---|
| 34 | return 0; |
|---|
| 35 | } |
|---|
| 36 | |
|---|
| 37 | void abs_lowcore_unmap(int cpu) |
|---|
| 38 | { |
|---|
| 39 | unsigned long addr = __abs_lowcore + (cpu * sizeof(struct lowcore)); |
|---|
| 40 | int i; |
|---|
| 41 | |
|---|
| 42 | for (i = 0; i < LC_PAGES; i++) { |
|---|
| 43 | vmem_unmap_4k_page(addr); |
|---|
| 44 | addr += PAGE_SIZE; |
|---|
| 45 | } |
|---|
| 46 | } |
|---|
| 47 | |
|---|
