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Diffstat (limited to 'arch/arm64/kernel/hibernate.c')
-rw-r--r--arch/arm64/kernel/hibernate.c118
1 files changed, 82 insertions, 36 deletions
diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c
index 65d81f965e74..d55a7b09959b 100644
--- a/arch/arm64/kernel/hibernate.c
+++ b/arch/arm64/kernel/hibernate.c
@@ -15,9 +15,9 @@
* License terms: GNU General Public License (GPL) version 2
*/
#define pr_fmt(x) "hibernate: " x
+#include <linux/cpu.h>
#include <linux/kvm_host.h>
#include <linux/mm.h>
-#include <linux/notifier.h>
#include <linux/pm.h>
#include <linux/sched.h>
#include <linux/suspend.h>
@@ -26,6 +26,7 @@
#include <asm/barrier.h>
#include <asm/cacheflush.h>
+#include <asm/cputype.h>
#include <asm/irqflags.h>
#include <asm/memory.h>
#include <asm/mmu_context.h>
@@ -34,6 +35,7 @@
#include <asm/pgtable-hwdef.h>
#include <asm/sections.h>
#include <asm/smp.h>
+#include <asm/smp_plat.h>
#include <asm/suspend.h>
#include <asm/sysreg.h>
#include <asm/virt.h>
@@ -54,12 +56,6 @@ extern int in_suspend;
/* Do we need to reset el2? */
#define el2_reset_needed() (is_hyp_mode_available() && !is_kernel_in_hyp_mode())
-/*
- * Start/end of the hibernate exit code, this must be copied to a 'safe'
- * location in memory, and executed from there.
- */
-extern char __hibernate_exit_text_start[], __hibernate_exit_text_end[];
-
/* temporary el2 vectors in the __hibernate_exit_text section. */
extern char hibernate_el2_vectors[];
@@ -67,6 +63,12 @@ extern char hibernate_el2_vectors[];
extern char __hyp_stub_vectors[];
/*
+ * The logical cpu number we should resume on, initialised to a non-cpu
+ * number.
+ */
+static int sleep_cpu = -EINVAL;
+
+/*
* Values that may not change over hibernate/resume. We put the build number
* and date in here so that we guarantee not to resume with a different
* kernel.
@@ -88,6 +90,8 @@ static struct arch_hibernate_hdr {
* re-configure el2.
*/
phys_addr_t __hyp_stub_vectors;
+
+ u64 sleep_cpu_mpidr;
} resume_hdr;
static inline void arch_hdr_invariants(struct arch_hibernate_hdr_invariants *i)
@@ -130,12 +134,22 @@ int arch_hibernation_header_save(void *addr, unsigned int max_size)
else
hdr->__hyp_stub_vectors = 0;
+ /* Save the mpidr of the cpu we called cpu_suspend() on... */
+ if (sleep_cpu < 0) {
+ pr_err("Failing to hibernate on an unkown CPU.\n");
+ return -ENODEV;
+ }
+ hdr->sleep_cpu_mpidr = cpu_logical_map(sleep_cpu);
+ pr_info("Hibernating on CPU %d [mpidr:0x%llx]\n", sleep_cpu,
+ hdr->sleep_cpu_mpidr);
+
return 0;
}
EXPORT_SYMBOL(arch_hibernation_header_save);
int arch_hibernation_header_restore(void *addr)
{
+ int ret;
struct arch_hibernate_hdr_invariants invariants;
struct arch_hibernate_hdr *hdr = addr;
@@ -145,6 +159,24 @@ int arch_hibernation_header_restore(void *addr)
return -EINVAL;
}
+ sleep_cpu = get_logical_index(hdr->sleep_cpu_mpidr);
+ pr_info("Hibernated on CPU %d [mpidr:0x%llx]\n", sleep_cpu,
+ hdr->sleep_cpu_mpidr);
+ if (sleep_cpu < 0) {
+ pr_crit("Hibernated on a CPU not known to this kernel!\n");
+ sleep_cpu = -EINVAL;
+ return -EINVAL;
+ }
+ if (!cpu_online(sleep_cpu)) {
+ pr_info("Hibernated on a CPU that is offline! Bringing CPU up.\n");
+ ret = cpu_up(sleep_cpu);
+ if (ret) {
+ pr_err("Failed to bring hibernate-CPU up!\n");
+ sleep_cpu = -EINVAL;
+ return ret;
+ }
+ }
+
resume_hdr = *hdr;
return 0;
@@ -241,6 +273,7 @@ out:
return rc;
}
+#define dcache_clean_range(start, end) __flush_dcache_area(start, (end - start))
int swsusp_arch_suspend(void)
{
@@ -256,10 +289,16 @@ int swsusp_arch_suspend(void)
local_dbg_save(flags);
if (__cpu_suspend_enter(&state)) {
+ sleep_cpu = smp_processor_id();
ret = swsusp_save();
} else {
- /* Clean kernel to PoC for secondary core startup */
- __flush_dcache_area(LMADDR(KERNEL_START), KERNEL_END - KERNEL_START);
+ /* Clean kernel core startup/idle code to PoC*/
+ dcache_clean_range(__mmuoff_data_start, __mmuoff_data_end);
+ dcache_clean_range(__idmap_text_start, __idmap_text_end);
+
+ /* Clean kvm setup code to PoC? */
+ if (el2_reset_needed())
+ dcache_clean_range(__hyp_idmap_text_start, __hyp_idmap_text_end);
/*
* Tell the hibernation core that we've just restored
@@ -267,6 +306,7 @@ int swsusp_arch_suspend(void)
*/
in_suspend = 0;
+ sleep_cpu = -EINVAL;
__cpu_suspend_exit();
}
@@ -275,6 +315,33 @@ int swsusp_arch_suspend(void)
return ret;
}
+static void _copy_pte(pte_t *dst_pte, pte_t *src_pte, unsigned long addr)
+{
+ pte_t pte = *src_pte;
+
+ if (pte_valid(pte)) {
+ /*
+ * Resume will overwrite areas that may be marked
+ * read only (code, rodata). Clear the RDONLY bit from
+ * the temporary mappings we use during restore.
+ */
+ set_pte(dst_pte, pte_clear_rdonly(pte));
+ } else if (debug_pagealloc_enabled() && !pte_none(pte)) {
+ /*
+ * debug_pagealloc will removed the PTE_VALID bit if
+ * the page isn't in use by the resume kernel. It may have
+ * been in use by the original kernel, in which case we need
+ * to put it back in our copy to do the restore.
+ *
+ * Before marking this entry valid, check the pfn should
+ * be mapped.
+ */
+ BUG_ON(!pfn_valid(pte_pfn(pte)));
+
+ set_pte(dst_pte, pte_mkpresent(pte_clear_rdonly(pte)));
+ }
+}
+
static int copy_pte(pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long start,
unsigned long end)
{
@@ -290,13 +357,7 @@ static int copy_pte(pmd_t *dst_pmd, pmd_t *src_pmd, unsigned long start,
src_pte = pte_offset_kernel(src_pmd, start);
do {
- if (!pte_none(*src_pte))
- /*
- * Resume will overwrite areas that may be marked
- * read only (code, rodata). Clear the RDONLY bit from
- * the temporary mappings we use during restore.
- */
- set_pte(dst_pte, __pte(pte_val(*src_pte) & ~PTE_RDONLY));
+ _copy_pte(dst_pte, src_pte, addr);
} while (dst_pte++, src_pte++, addr += PAGE_SIZE, addr != end);
return 0;
@@ -483,27 +544,12 @@ out:
return rc;
}
-static int check_boot_cpu_online_pm_callback(struct notifier_block *nb,
- unsigned long action, void *ptr)
+int hibernate_resume_nonboot_cpu_disable(void)
{
- if (action == PM_HIBERNATION_PREPARE &&
- cpumask_first(cpu_online_mask) != 0) {
- pr_warn("CPU0 is offline.\n");
- return notifier_from_errno(-ENODEV);
+ if (sleep_cpu < 0) {
+ pr_err("Failing to resume from hibernate on an unkown CPU.\n");
+ return -ENODEV;
}
- return NOTIFY_OK;
-}
-
-static int __init check_boot_cpu_online_init(void)
-{
- /*
- * Set this pm_notifier callback with a lower priority than
- * cpu_hotplug_pm_callback, so that cpu_hotplug_pm_callback will be
- * called earlier to disable cpu hotplug before the cpu online check.
- */
- pm_notifier(check_boot_cpu_online_pm_callback, -INT_MAX);
-
- return 0;
+ return freeze_secondary_cpus(sleep_cpu);
}
-core_initcall(check_boot_cpu_online_init);