[PATCH 2/3] x86, hibernate: Extract the common code of 64/32 bit system

From: Gu Zhimin
Date: Mon Aug 27 2018 - 05:26:00 EST


From: Zhimin Gu <kookoo.gu@xxxxxxxxx>

Reduce the hibernation code duplication between x86-32 and x86-64
by extracting the common code into hibernate.c.

No functional change.

Suggested-by: Pavel Machek <pavel@xxxxxx>
Acked-by: Chen Yu <yu.c.chen@xxxxxxxxx>
Signed-off-by: Zhimin Gu <kookoo.gu@xxxxxxxxx>
---
arch/x86/power/hibernate.c | 255 ++++++++++++++++++++++++++++++++++++++
arch/x86/power/hibernate_32.c | 22 +---
arch/x86/power/hibernate_64.c | 241 +----------------------------------
arch/x86/power/hibernate_asm_64.S | 2 +-
4 files changed, 259 insertions(+), 261 deletions(-)
create mode 100644 arch/x86/power/hibernate.c

diff --git a/arch/x86/power/hibernate.c b/arch/x86/power/hibernate.c
new file mode 100644
index 0000000..6f91f7b
--- /dev/null
+++ b/arch/x86/power/hibernate.c
@@ -0,0 +1,255 @@
+/*
+ * Hibernation support for x86
+ *
+ * Distribute under GPLv2
+ *
+ * Copyright (c) 2007 Rafael J. Wysocki <rjw@xxxxxxx>
+ * Copyright (c) 2002 Pavel Machek <pavel@xxxxxx>
+ * Copyright (c) 2001 Patrick Mochel <mochel@xxxxxxxx>
+ */
+
+#include <linux/gfp.h>
+#include <linux/smp.h>
+#include <linux/suspend.h>
+#include <linux/scatterlist.h>
+#include <linux/kdebug.h>
+#include <linux/bootmem.h>
+
+#include <crypto/hash.h>
+
+#include <asm/e820/api.h>
+#include <asm/init.h>
+#include <asm/proto.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/mtrr.h>
+#include <asm/sections.h>
+#include <asm/suspend.h>
+#include <asm/tlbflush.h>
+#include <asm/mmzone.h>
+
+/* Defined in hibernate_asm_64.S or hibernate_asm_32.S */
+extern asmlinkage __visible int restore_image(void);
+
+/*
+ * Address to jump to in the last phase of restore in order to get to the image
+ * kernel's text (this value is passed in the image header).
+ */
+unsigned long restore_jump_address __visible;
+unsigned long jump_address_phys;
+
+/*
+ * Value of the cr3 register from before the hibernation (this value is passed
+ * in the image header).
+ */
+unsigned long restore_cr3 __visible;
+unsigned long temp_pgt __visible;
+unsigned long relocated_restore_code __visible;
+
+#ifdef CONFIG_X86_32
+ #define RESTORE_MAGIC 0x12345678UL
+#else
+ #define RESTORE_MAGIC 0x23456789ABCDEF01UL
+#endif
+
+/*
+ * pfn_is_nosave - check if given pfn is in the 'nosave' section
+ */
+
+int pfn_is_nosave(unsigned long pfn)
+{
+ unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT;
+ unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT;
+ return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
+}
+
+#ifdef CONFIG_X86_64
+static int relocate_restore_code(void)
+{
+ pgd_t *pgd;
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+
+ relocated_restore_code = get_safe_page(GFP_ATOMIC);
+ if (!relocated_restore_code)
+ return -ENOMEM;
+
+ memcpy((void *)relocated_restore_code, core_restore_code, PAGE_SIZE);
+
+ /* Make the page containing the relocated code executable */
+ pgd = (pgd_t *)__va(read_cr3_pa()) +
+ pgd_index(relocated_restore_code);
+ p4d = p4d_offset(pgd, relocated_restore_code);
+ if (p4d_large(*p4d)) {
+ set_p4d(p4d, __p4d(p4d_val(*p4d) & ~_PAGE_NX));
+ goto out;
+ }
+ pud = pud_offset(p4d, relocated_restore_code);
+ if (pud_large(*pud)) {
+ set_pud(pud, __pud(pud_val(*pud) & ~_PAGE_NX));
+ goto out;
+ }
+ pmd = pmd_offset(pud, relocated_restore_code);
+ if (pmd_large(*pmd)) {
+ set_pmd(pmd, __pmd(pmd_val(*pmd) & ~_PAGE_NX));
+ goto out;
+ }
+ pte = pte_offset_kernel(pmd, relocated_restore_code);
+ set_pte(pte, __pte(pte_val(*pte) & ~_PAGE_NX));
+out:
+ __flush_tlb_all();
+ return 0;
+}
+
+#define MD5_DIGEST_SIZE 16
+
+struct restore_data_record {
+ unsigned long jump_address;
+ unsigned long jump_address_phys;
+ unsigned long cr3;
+ unsigned long magic;
+ u8 e820_digest[MD5_DIGEST_SIZE];
+};
+
+#if IS_BUILTIN(CONFIG_CRYPTO_MD5)
+/**
+ * get_e820_md5 - calculate md5 according to given e820 table
+ *
+ * @table: the e820 table to be calculated
+ * @buf: the md5 result to be stored to
+ */
+static int get_e820_md5(struct e820_table *table, void *buf)
+{
+ struct crypto_shash *tfm;
+ struct shash_desc *desc;
+ int size;
+ int ret = 0;
+
+ tfm = crypto_alloc_shash("md5", 0, 0);
+ if (IS_ERR(tfm))
+ return -ENOMEM;
+
+ desc = kmalloc(sizeof(struct shash_desc) + crypto_shash_descsize(tfm),
+ GFP_KERNEL);
+ if (!desc) {
+ ret = -ENOMEM;
+ goto free_tfm;
+ }
+
+ desc->tfm = tfm;
+ desc->flags = 0;
+
+ size = offsetof(struct e820_table, entries) +
+ sizeof(struct e820_entry) * table->nr_entries;
+
+ if (crypto_shash_digest(desc, (u8 *)table, size, buf))
+ ret = -EINVAL;
+
+ kzfree(desc);
+
+free_tfm:
+ crypto_free_shash(tfm);
+ return ret;
+}
+
+static void hibernation_e820_save(void *buf)
+{
+ get_e820_md5(e820_table_firmware, buf);
+}
+
+static bool hibernation_e820_mismatch(void *buf)
+{
+ int ret;
+ u8 result[MD5_DIGEST_SIZE];
+
+ memset(result, 0, MD5_DIGEST_SIZE);
+ /* If there is no digest in suspend kernel, let it go. */
+ if (!memcmp(result, buf, MD5_DIGEST_SIZE))
+ return false;
+
+ ret = get_e820_md5(e820_table_firmware, result);
+ if (ret)
+ return true;
+
+ return memcmp(result, buf, MD5_DIGEST_SIZE) ? true : false;
+}
+#else
+static void hibernation_e820_save(void *buf)
+{
+}
+
+static bool hibernation_e820_mismatch(void *buf)
+{
+ /* If md5 is not builtin for restore kernel, let it go. */
+ return false;
+}
+#endif
+
+/**
+ * arch_hibernation_header_save - populate the architecture specific part
+ * of a hibernation image header
+ * @addr: address to save the data at
+ */
+int arch_hibernation_header_save(void *addr, unsigned int max_size)
+{
+ struct restore_data_record *rdr = addr;
+
+ if (max_size < sizeof(struct restore_data_record))
+ return -EOVERFLOW;
+ rdr->jump_address = (unsigned long)restore_registers;
+ rdr->jump_address_phys = __pa_symbol(restore_registers);
+
+ /*
+ * The restore code fixes up CR3 and CR4 in the following sequence:
+ *
+ * [in hibernation asm]
+ * 1. CR3 <= temporary page tables
+ * 2. CR4 <= mmu_cr4_features (from the kernel that restores us)
+ * 3. CR3 <= rdr->cr3
+ * 4. CR4 <= mmu_cr4_features (from us, i.e. the image kernel)
+ * [in restore_processor_state()]
+ * 5. CR4 <= saved CR4
+ * 6. CR3 <= saved CR3
+ *
+ * Our mmu_cr4_features has CR4.PCIDE=0, and toggling
+ * CR4.PCIDE while CR3's PCID bits are nonzero is illegal, so
+ * rdr->cr3 needs to point to valid page tables but must not
+ * have any of the PCID bits set.
+ */
+ rdr->cr3 = restore_cr3 & ~CR3_PCID_MASK;
+
+ rdr->magic = RESTORE_MAGIC;
+
+ hibernation_e820_save(rdr->e820_digest);
+
+ return 0;
+}
+
+/**
+ * arch_hibernation_header_restore - read the architecture specific data
+ * from the hibernation image header
+ * @addr: address to read the data from
+ */
+int arch_hibernation_header_restore(void *addr)
+{
+ struct restore_data_record *rdr = addr;
+
+ restore_jump_address = rdr->jump_address;
+ jump_address_phys = rdr->jump_address_phys;
+ restore_cr3 = rdr->cr3;
+
+ if (rdr->magic != RESTORE_MAGIC) {
+ pr_crit("Unrecognized hibernate image header format!\n");
+ return -EINVAL;
+ }
+
+ if (hibernation_e820_mismatch(rdr->e820_digest)) {
+ pr_crit("Hibernate inconsistent memory map detected!\n");
+ return -ENODEV;
+ }
+
+ return 0;
+}
+#endif
diff --git a/arch/x86/power/hibernate_32.c b/arch/x86/power/hibernate_32.c
index afc4ed7..7922e11 100644
--- a/arch/x86/power/hibernate_32.c
+++ b/arch/x86/power/hibernate_32.c
@@ -6,17 +6,7 @@
* Copyright (c) 2006 Rafael J. Wysocki <rjw@xxxxxxx>
*/

-#include <linux/gfp.h>
-#include <linux/suspend.h>
-#include <linux/bootmem.h>
-
-#include <asm/page.h>
-#include <asm/pgtable.h>
-#include <asm/mmzone.h>
-#include <asm/sections.h>
-
-/* Defined in hibernate_asm_32.S */
-extern int restore_image(void);
+#include "hibernate.c"

/* Pointer to the temporary resume page tables */
pgd_t *resume_pg_dir;
@@ -163,13 +153,3 @@ asmlinkage int swsusp_arch_resume(void)
return 0;
}

-/*
- * pfn_is_nosave - check if given pfn is in the 'nosave' section
- */
-
-int pfn_is_nosave(unsigned long pfn)
-{
- unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT;
- unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT;
- return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
-}
diff --git a/arch/x86/power/hibernate_64.c b/arch/x86/power/hibernate_64.c
index f8e3b66..77037c3 100644
--- a/arch/x86/power/hibernate_64.c
+++ b/arch/x86/power/hibernate_64.c
@@ -8,43 +8,7 @@
* Copyright (c) 2001 Patrick Mochel <mochel@xxxxxxxx>
*/

-#include <linux/gfp.h>
-#include <linux/smp.h>
-#include <linux/suspend.h>
-#include <linux/scatterlist.h>
-#include <linux/kdebug.h>
-
-#include <crypto/hash.h>
-
-#include <asm/e820/api.h>
-#include <asm/init.h>
-#include <asm/proto.h>
-#include <asm/page.h>
-#include <asm/pgtable.h>
-#include <asm/mtrr.h>
-#include <asm/sections.h>
-#include <asm/suspend.h>
-#include <asm/tlbflush.h>
-
-/* Defined in hibernate_asm_64.S */
-extern asmlinkage __visible int restore_image(void);
-
-/*
- * Address to jump to in the last phase of restore in order to get to the image
- * kernel's text (this value is passed in the image header).
- */
-unsigned long restore_jump_address __visible;
-unsigned long jump_address_phys;
-
-/*
- * Value of the cr3 register from before the hibernation (this value is passed
- * in the image header).
- */
-unsigned long restore_cr3 __visible;
-
-unsigned long temp_level4_pgt __visible;
-
-unsigned long relocated_restore_code __visible;
+#include "hibernate.c"

static int set_up_temporary_text_mapping(pgd_t *pgd)
{
@@ -141,46 +105,7 @@ static int set_up_temporary_mappings(void)
return result;
}

- temp_level4_pgt = __pa(pgd);
- return 0;
-}
-
-static int relocate_restore_code(void)
-{
- pgd_t *pgd;
- p4d_t *p4d;
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
-
- relocated_restore_code = get_safe_page(GFP_ATOMIC);
- if (!relocated_restore_code)
- return -ENOMEM;
-
- memcpy((void *)relocated_restore_code, core_restore_code, PAGE_SIZE);
-
- /* Make the page containing the relocated code executable */
- pgd = (pgd_t *)__va(read_cr3_pa()) +
- pgd_index(relocated_restore_code);
- p4d = p4d_offset(pgd, relocated_restore_code);
- if (p4d_large(*p4d)) {
- set_p4d(p4d, __p4d(p4d_val(*p4d) & ~_PAGE_NX));
- goto out;
- }
- pud = pud_offset(p4d, relocated_restore_code);
- if (pud_large(*pud)) {
- set_pud(pud, __pud(pud_val(*pud) & ~_PAGE_NX));
- goto out;
- }
- pmd = pmd_offset(pud, relocated_restore_code);
- if (pmd_large(*pmd)) {
- set_pmd(pmd, __pmd(pmd_val(*pmd) & ~_PAGE_NX));
- goto out;
- }
- pte = pte_offset_kernel(pmd, relocated_restore_code);
- set_pte(pte, __pte(pte_val(*pte) & ~_PAGE_NX));
-out:
- __flush_tlb_all();
+ temp_pgt = __pa(pgd);
return 0;
}

@@ -201,165 +126,3 @@ asmlinkage int swsusp_arch_resume(void)
return 0;
}

-/*
- * pfn_is_nosave - check if given pfn is in the 'nosave' section
- */
-
-int pfn_is_nosave(unsigned long pfn)
-{
- unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT;
- unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT;
- return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
-}
-
-#define MD5_DIGEST_SIZE 16
-
-struct restore_data_record {
- unsigned long jump_address;
- unsigned long jump_address_phys;
- unsigned long cr3;
- unsigned long magic;
- u8 e820_digest[MD5_DIGEST_SIZE];
-};
-
-#define RESTORE_MAGIC 0x23456789ABCDEF01UL
-
-#if IS_BUILTIN(CONFIG_CRYPTO_MD5)
-/**
- * get_e820_md5 - calculate md5 according to given e820 table
- *
- * @table: the e820 table to be calculated
- * @buf: the md5 result to be stored to
- */
-static int get_e820_md5(struct e820_table *table, void *buf)
-{
- struct crypto_shash *tfm;
- struct shash_desc *desc;
- int size;
- int ret = 0;
-
- tfm = crypto_alloc_shash("md5", 0, 0);
- if (IS_ERR(tfm))
- return -ENOMEM;
-
- desc = kmalloc(sizeof(struct shash_desc) + crypto_shash_descsize(tfm),
- GFP_KERNEL);
- if (!desc) {
- ret = -ENOMEM;
- goto free_tfm;
- }
-
- desc->tfm = tfm;
- desc->flags = 0;
-
- size = offsetof(struct e820_table, entries) +
- sizeof(struct e820_entry) * table->nr_entries;
-
- if (crypto_shash_digest(desc, (u8 *)table, size, buf))
- ret = -EINVAL;
-
- kzfree(desc);
-
-free_tfm:
- crypto_free_shash(tfm);
- return ret;
-}
-
-static void hibernation_e820_save(void *buf)
-{
- get_e820_md5(e820_table_firmware, buf);
-}
-
-static bool hibernation_e820_mismatch(void *buf)
-{
- int ret;
- u8 result[MD5_DIGEST_SIZE];
-
- memset(result, 0, MD5_DIGEST_SIZE);
- /* If there is no digest in suspend kernel, let it go. */
- if (!memcmp(result, buf, MD5_DIGEST_SIZE))
- return false;
-
- ret = get_e820_md5(e820_table_firmware, result);
- if (ret)
- return true;
-
- return memcmp(result, buf, MD5_DIGEST_SIZE) ? true : false;
-}
-#else
-static void hibernation_e820_save(void *buf)
-{
-}
-
-static bool hibernation_e820_mismatch(void *buf)
-{
- /* If md5 is not builtin for restore kernel, let it go. */
- return false;
-}
-#endif
-
-/**
- * arch_hibernation_header_save - populate the architecture specific part
- * of a hibernation image header
- * @addr: address to save the data at
- */
-int arch_hibernation_header_save(void *addr, unsigned int max_size)
-{
- struct restore_data_record *rdr = addr;
-
- if (max_size < sizeof(struct restore_data_record))
- return -EOVERFLOW;
- rdr->jump_address = (unsigned long)restore_registers;
- rdr->jump_address_phys = __pa_symbol(restore_registers);
-
- /*
- * The restore code fixes up CR3 and CR4 in the following sequence:
- *
- * [in hibernation asm]
- * 1. CR3 <= temporary page tables
- * 2. CR4 <= mmu_cr4_features (from the kernel that restores us)
- * 3. CR3 <= rdr->cr3
- * 4. CR4 <= mmu_cr4_features (from us, i.e. the image kernel)
- * [in restore_processor_state()]
- * 5. CR4 <= saved CR4
- * 6. CR3 <= saved CR3
- *
- * Our mmu_cr4_features has CR4.PCIDE=0, and toggling
- * CR4.PCIDE while CR3's PCID bits are nonzero is illegal, so
- * rdr->cr3 needs to point to valid page tables but must not
- * have any of the PCID bits set.
- */
- rdr->cr3 = restore_cr3 & ~CR3_PCID_MASK;
-
- rdr->magic = RESTORE_MAGIC;
-
- hibernation_e820_save(rdr->e820_digest);
-
- return 0;
-}
-
-/**
- * arch_hibernation_header_restore - read the architecture specific data
- * from the hibernation image header
- * @addr: address to read the data from
- */
-int arch_hibernation_header_restore(void *addr)
-{
- struct restore_data_record *rdr = addr;
-
- restore_jump_address = rdr->jump_address;
- jump_address_phys = rdr->jump_address_phys;
- restore_cr3 = rdr->cr3;
-
- if (rdr->magic != RESTORE_MAGIC) {
- pr_crit("Unrecognized hibernate image header format!\n");
- return -EINVAL;
- }
-
- if (hibernation_e820_mismatch(rdr->e820_digest)) {
- pr_crit("Hibernate inconsistent memory map detected!\n");
- return -ENODEV;
- }
-
- return 0;
-}
diff --git a/arch/x86/power/hibernate_asm_64.S b/arch/x86/power/hibernate_asm_64.S
index fd369a6..3008baa 100644
--- a/arch/x86/power/hibernate_asm_64.S
+++ b/arch/x86/power/hibernate_asm_64.S
@@ -59,7 +59,7 @@ ENTRY(restore_image)
movq restore_cr3(%rip), %r9

/* prepare to switch to temporary page tables */
- movq temp_level4_pgt(%rip), %rax
+ movq temp_pgt(%rip), %rax
movq mmu_cr4_features(%rip), %rbx

/* prepare to copy image data to their original locations */
--
2.7.4