* 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>
#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>
#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>
/*
/* 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[];
/* hyp-stub vectors, used to restore el2 during resume from hibernate. */
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
* 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)
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;
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;
set_pte(pte, __pte(virt_to_phys((void *)dst) |
pgprot_val(PAGE_KERNEL_EXEC)));
- /* Load our new page tables */
- asm volatile("msr ttbr0_el1, %0;"
- "isb;"
- "tlbi vmalle1is;"
- "dsb ish;"
- "isb" : : "r"(virt_to_phys(pgd)));
+ /*
+ * Load our new page tables. A strict BBM approach requires that we
+ * ensure that TLBs are free of any entries that may overlap with the
+ * global mappings we are about to install.
+ *
+ * For a real hibernate/resume cycle TTBR0 currently points to a zero
+ * page, but TLBs may contain stale ASID-tagged entries (e.g. for EFI
+ * runtime services), while for a userspace-driven test_resume cycle it
+ * points to userspace page tables (and we must point it at a zero page
+ * ourselves). Elsewhere we only (un)install the idmap with preemption
+ * disabled, so T0SZ should be as required regardless.
+ */
+ cpu_set_reserved_ttbr0();
+ local_flush_tlb_all();
+ write_sysreg(virt_to_phys(pgd), ttbr0_el1);
+ isb();
*phys_dst_addr = virt_to_phys((void *)dst);
return rc;
}
+#define dcache_clean_range(start, end) __flush_dcache_area(start, (end - start))
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
*/
in_suspend = 0;
+ sleep_cpu = -EINVAL;
__cpu_suspend_exit();
}
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)
{
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;
void __noreturn (*hibernate_exit)(phys_addr_t, phys_addr_t, void *,
void *, phys_addr_t, phys_addr_t);
+ /*
+ * Restoring the memory image will overwrite the ttbr1 page tables.
+ * Create a second copy of just the linear map, and use this when
+ * restoring.
+ */
+ tmp_pg_dir = (pgd_t *)get_safe_page(GFP_ATOMIC);
+ if (!tmp_pg_dir) {
+ pr_err("Failed to allocate memory for temporary page tables.");
+ rc = -ENOMEM;
+ goto out;
+ }
+ rc = copy_page_tables(tmp_pg_dir, PAGE_OFFSET, 0);
+ if (rc)
+ goto out;
+
+ /*
+ * Since we only copied the linear map, we need to find restore_pblist's
+ * linear map address.
+ */
+ lm_restore_pblist = LMADDR(restore_pblist);
+
+ /*
+ * We need a zero page that is zero before & after resume in order to
+ * to break before make on the ttbr1 page tables.
+ */
+ zero_page = (void *)get_safe_page(GFP_ATOMIC);
+ if (!zero_page) {
+ pr_err("Failed to allocate zero page.");
+ rc = -ENOMEM;
+ goto out;
+ }
+
/*
* Locate the exit code in the bottom-but-one page, so that *NULL
* still has disastrous affects.
*/
__flush_dcache_area(hibernate_exit, exit_size);
- /*
- * Restoring the memory image will overwrite the ttbr1 page tables.
- * Create a second copy of just the linear map, and use this when
- * restoring.
- */
- tmp_pg_dir = (pgd_t *)get_safe_page(GFP_ATOMIC);
- if (!tmp_pg_dir) {
- pr_err("Failed to allocate memory for temporary page tables.");
- rc = -ENOMEM;
- goto out;
- }
- rc = copy_page_tables(tmp_pg_dir, PAGE_OFFSET, 0);
- if (rc)
- goto out;
-
- /*
- * Since we only copied the linear map, we need to find restore_pblist's
- * linear map address.
- */
- lm_restore_pblist = LMADDR(restore_pblist);
-
/*
* KASLR will cause the el2 vectors to be in a different location in
* the resumed kernel. Load hibernate's temporary copy into el2.
__hyp_set_vectors(el2_vectors);
}
- /*
- * We need a zero page that is zero before & after resume in order to
- * to break before make on the ttbr1 page tables.
- */
- zero_page = (void *)get_safe_page(GFP_ATOMIC);
-
hibernate_exit(virt_to_phys(tmp_pg_dir), resume_hdr.ttbr1_el1,
resume_hdr.reenter_kernel, lm_restore_pblist,
resume_hdr.__hyp_stub_vectors, virt_to_phys(zero_page));
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);
projects / cascardo / linux.git / blobdiff