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-rw-r--r--Documentation/kernel-parameters.txt3
-rw-r--r--arch/x86/include/asm/smp.h1
-rw-r--r--arch/x86/kernel/smpboot.c2
-rw-r--r--arch/x86/power/cpu.c30
-rw-r--r--include/linux/suspend.h5
-rw-r--r--kernel/power/Makefile2
-rw-r--r--kernel/power/console.c8
-rw-r--r--kernel/power/hibernate.c101
-rw-r--r--kernel/power/main.c11
-rw-r--r--kernel/power/power.h11
-rw-r--r--kernel/power/process.c3
-rw-r--r--kernel/power/snapshot.c940
-rw-r--r--kernel/power/suspend.c10
-rw-r--r--kernel/power/swap.c6
-rw-r--r--kernel/power/user.c14
-rw-r--r--kernel/workqueue.c4
-rwxr-xr-xscripts/analyze_suspend.py3641
-rw-r--r--tools/power/x86/turbostat/Makefile4
18 files changed, 3147 insertions, 1649 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 82b42c958d1c..07960c24642d 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -3594,6 +3594,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
present during boot.
nocompress Don't compress/decompress hibernation images.
no Disable hibernation and resume.
+ protect_image Turn on image protection during restoration
+ (that will set all pages holding image data
+ during restoration read-only).
retain_initrd [RAM] Keep initrd memory after extraction
diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h
index 66b057306f40..7427ca895a27 100644
--- a/arch/x86/include/asm/smp.h
+++ b/arch/x86/include/asm/smp.h
@@ -135,6 +135,7 @@ int native_cpu_up(unsigned int cpunum, struct task_struct *tidle);
int native_cpu_disable(void);
int common_cpu_die(unsigned int cpu);
void native_cpu_die(unsigned int cpu);
+void hlt_play_dead(void);
void native_play_dead(void);
void play_dead_common(void);
void wbinvd_on_cpu(int cpu);
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index fafe8b923cac..8264dfad9cf8 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -1622,7 +1622,7 @@ static inline void mwait_play_dead(void)
}
}
-static inline void hlt_play_dead(void)
+void hlt_play_dead(void)
{
if (__this_cpu_read(cpu_info.x86) >= 4)
wbinvd();
diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c
index d5f64996394a..b12c26e2e309 100644
--- a/arch/x86/power/cpu.c
+++ b/arch/x86/power/cpu.c
@@ -12,6 +12,7 @@
#include <linux/export.h>
#include <linux/smp.h>
#include <linux/perf_event.h>
+#include <linux/tboot.h>
#include <asm/pgtable.h>
#include <asm/proto.h>
@@ -266,6 +267,35 @@ void notrace restore_processor_state(void)
EXPORT_SYMBOL(restore_processor_state);
#endif
+#if defined(CONFIG_HIBERNATION) && defined(CONFIG_HOTPLUG_CPU)
+static void resume_play_dead(void)
+{
+ play_dead_common();
+ tboot_shutdown(TB_SHUTDOWN_WFS);
+ hlt_play_dead();
+}
+
+int hibernate_resume_nonboot_cpu_disable(void)
+{
+ void (*play_dead)(void) = smp_ops.play_dead;
+ int ret;
+
+ /*
+ * Ensure that MONITOR/MWAIT will not be used in the "play dead" loop
+ * during hibernate image restoration, because it is likely that the
+ * monitored address will be actually written to at that time and then
+ * the "dead" CPU will attempt to execute instructions again, but the
+ * address in its instruction pointer may not be possible to resolve
+ * any more at that point (the page tables used by it previously may
+ * have been overwritten by hibernate image data).
+ */
+ smp_ops.play_dead = resume_play_dead;
+ ret = disable_nonboot_cpus();
+ smp_ops.play_dead = play_dead;
+ return ret;
+}
+#endif
+
/*
* When bsp_check() is called in hibernate and suspend, cpu hotplug
* is disabled already. So it's unnessary to handle race condition between
diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index 8b6ec7ef0854..7693e39b14fe 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -18,12 +18,11 @@ static inline void pm_set_vt_switch(int do_switch)
#endif
#ifdef CONFIG_VT_CONSOLE_SLEEP
-extern int pm_prepare_console(void);
+extern void pm_prepare_console(void);
extern void pm_restore_console(void);
#else
-static inline int pm_prepare_console(void)
+static inline void pm_prepare_console(void)
{
- return 0;
}
static inline void pm_restore_console(void)
diff --git a/kernel/power/Makefile b/kernel/power/Makefile
index cb880a14cc39..eb4f717705ba 100644
--- a/kernel/power/Makefile
+++ b/kernel/power/Makefile
@@ -1,6 +1,8 @@
ccflags-$(CONFIG_PM_DEBUG) := -DDEBUG
+KASAN_SANITIZE_snapshot.o := n
+
obj-y += qos.o
obj-$(CONFIG_PM) += main.o
obj-$(CONFIG_VT_CONSOLE_SLEEP) += console.o
diff --git a/kernel/power/console.c b/kernel/power/console.c
index aba9c545a0e3..0e781798b0b3 100644
--- a/kernel/power/console.c
+++ b/kernel/power/console.c
@@ -126,17 +126,17 @@ out:
return ret;
}
-int pm_prepare_console(void)
+void pm_prepare_console(void)
{
if (!pm_vt_switch())
- return 0;
+ return;
orig_fgconsole = vt_move_to_console(SUSPEND_CONSOLE, 1);
if (orig_fgconsole < 0)
- return 1;
+ return;
orig_kmsg = vt_kmsg_redirect(SUSPEND_CONSOLE);
- return 0;
+ return;
}
void pm_restore_console(void)
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index fca9254280ee..0ee1df0a0bd6 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -52,6 +52,7 @@ enum {
#ifdef CONFIG_SUSPEND
HIBERNATION_SUSPEND,
#endif
+ HIBERNATION_TEST_RESUME,
/* keep last */
__HIBERNATION_AFTER_LAST
};
@@ -409,6 +410,11 @@ int hibernation_snapshot(int platform_mode)
goto Close;
}
+int __weak hibernate_resume_nonboot_cpu_disable(void)
+{
+ return disable_nonboot_cpus();
+}
+
/**
* resume_target_kernel - Restore system state from a hibernation image.
* @platform_mode: Whether or not to use the platform driver.
@@ -433,7 +439,7 @@ static int resume_target_kernel(bool platform_mode)
if (error)
goto Cleanup;
- error = disable_nonboot_cpus();
+ error = hibernate_resume_nonboot_cpu_disable();
if (error)
goto Enable_cpus;
@@ -642,12 +648,39 @@ static void power_down(void)
cpu_relax();
}
+static int load_image_and_restore(void)
+{
+ int error;
+ unsigned int flags;
+
+ pr_debug("PM: Loading hibernation image.\n");
+
+ lock_device_hotplug();
+ error = create_basic_memory_bitmaps();
+ if (error)
+ goto Unlock;
+
+ error = swsusp_read(&flags);
+ swsusp_close(FMODE_READ);
+ if (!error)
+ hibernation_restore(flags & SF_PLATFORM_MODE);
+
+ printk(KERN_ERR "PM: Failed to load hibernation image, recovering.\n");
+ swsusp_free();
+ free_basic_memory_bitmaps();
+ Unlock:
+ unlock_device_hotplug();
+
+ return error;
+}
+
/**
* hibernate - Carry out system hibernation, including saving the image.
*/
int hibernate(void)
{
- int error;
+ int error, nr_calls = 0;
+ bool snapshot_test = false;
if (!hibernation_available()) {
pr_debug("PM: Hibernation not available.\n");
@@ -662,9 +695,11 @@ int hibernate(void)
}
pm_prepare_console();
- error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
- if (error)
+ error = __pm_notifier_call_chain(PM_HIBERNATION_PREPARE, -1, &nr_calls);
+ if (error) {
+ nr_calls--;
goto Exit;
+ }
printk(KERN_INFO "PM: Syncing filesystems ... ");
sys_sync();
@@ -697,8 +732,12 @@ int hibernate(void)
pr_debug("PM: writing image.\n");
error = swsusp_write(flags);
swsusp_free();
- if (!error)
- power_down();
+ if (!error) {
+ if (hibernation_mode == HIBERNATION_TEST_RESUME)
+ snapshot_test = true;
+ else
+ power_down();
+ }
in_suspend = 0;
pm_restore_gfp_mask();
} else {
@@ -709,12 +748,18 @@ int hibernate(void)
free_basic_memory_bitmaps();
Thaw:
unlock_device_hotplug();
+ if (snapshot_test) {
+ pr_debug("PM: Checking hibernation image\n");
+ error = swsusp_check();
+ if (!error)
+ error = load_image_and_restore();
+ }
thaw_processes();
/* Don't bother checking whether freezer_test_done is true */
freezer_test_done = false;
Exit:
- pm_notifier_call_chain(PM_POST_HIBERNATION);
+ __pm_notifier_call_chain(PM_POST_HIBERNATION, nr_calls, NULL);
pm_restore_console();
atomic_inc(&snapshot_device_available);
Unlock:
@@ -740,8 +785,7 @@ int hibernate(void)
*/
static int software_resume(void)
{
- int error;
- unsigned int flags;
+ int error, nr_calls = 0;
/*
* If the user said "noresume".. bail out early.
@@ -827,35 +871,20 @@ static int software_resume(void)
}
pm_prepare_console();
- error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
- if (error)
+ error = __pm_notifier_call_chain(PM_RESTORE_PREPARE, -1, &nr_calls);
+ if (error) {
+ nr_calls--;
goto Close_Finish;
+ }
pr_debug("PM: Preparing processes for restore.\n");
error = freeze_processes();
if (error)
goto Close_Finish;
-
- pr_debug("PM: Loading hibernation image.\n");
-
- lock_device_hotplug();
- error = create_basic_memory_bitmaps();
- if (error)
- goto Thaw;
-
- error = swsusp_read(&flags);
- swsusp_close(FMODE_READ);
- if (!error)
- hibernation_restore(flags & SF_PLATFORM_MODE);
-
- printk(KERN_ERR "PM: Failed to load hibernation image, recovering.\n");
- swsusp_free();
- free_basic_memory_bitmaps();
- Thaw:
- unlock_device_hotplug();
+ error = load_image_and_restore();
thaw_processes();
Finish:
- pm_notifier_call_chain(PM_POST_RESTORE);
+ __pm_notifier_call_chain(PM_POST_RESTORE, nr_calls, NULL);
pm_restore_console();
atomic_inc(&snapshot_device_available);
/* For success case, the suspend path will release the lock */
@@ -878,6 +907,7 @@ static const char * const hibernation_modes[] = {
#ifdef CONFIG_SUSPEND
[HIBERNATION_SUSPEND] = "suspend",
#endif
+ [HIBERNATION_TEST_RESUME] = "test_resume",
};
/*
@@ -924,6 +954,7 @@ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
#ifdef CONFIG_SUSPEND
case HIBERNATION_SUSPEND:
#endif
+ case HIBERNATION_TEST_RESUME:
break;
case HIBERNATION_PLATFORM:
if (hibernation_ops)
@@ -970,6 +1001,7 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
#ifdef CONFIG_SUSPEND
case HIBERNATION_SUSPEND:
#endif
+ case HIBERNATION_TEST_RESUME:
hibernation_mode = mode;
break;
case HIBERNATION_PLATFORM:
@@ -1115,13 +1147,16 @@ static int __init resume_offset_setup(char *str)
static int __init hibernate_setup(char *str)
{
- if (!strncmp(str, "noresume", 8))
+ if (!strncmp(str, "noresume", 8)) {
noresume = 1;
- else if (!strncmp(str, "nocompress", 10))
+ } else if (!strncmp(str, "nocompress", 10)) {
nocompress = 1;
- else if (!strncmp(str, "no", 2)) {
+ } else if (!strncmp(str, "no", 2)) {
noresume = 1;
nohibernate = 1;
+ } else if (IS_ENABLED(CONFIG_DEBUG_RODATA)
+ && !strncmp(str, "protect_image", 13)) {
+ enable_restore_image_protection();
}
return 1;
}
diff --git a/kernel/power/main.c b/kernel/power/main.c
index 27946975eff0..5ea50b1b7595 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -38,12 +38,19 @@ int unregister_pm_notifier(struct notifier_block *nb)
}
EXPORT_SYMBOL_GPL(unregister_pm_notifier);
-int pm_notifier_call_chain(unsigned long val)
+int __pm_notifier_call_chain(unsigned long val, int nr_to_call, int *nr_calls)
{
- int ret = blocking_notifier_call_chain(&pm_chain_head, val, NULL);
+ int ret;
+
+ ret = __blocking_notifier_call_chain(&pm_chain_head, val, NULL,
+ nr_to_call, nr_calls);
return notifier_to_errno(ret);
}
+int pm_notifier_call_chain(unsigned long val)
+{
+ return __pm_notifier_call_chain(val, -1, NULL);
+}
/* If set, devices may be suspended and resumed asynchronously. */
int pm_async_enabled = 1;
diff --git a/kernel/power/power.h b/kernel/power/power.h
index efe1b3b17c88..242d8b827dd5 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -38,6 +38,8 @@ static inline char *check_image_kernel(struct swsusp_info *info)
}
#endif /* CONFIG_ARCH_HIBERNATION_HEADER */
+extern int hibernate_resume_nonboot_cpu_disable(void);
+
/*
* Keep some memory free so that I/O operations can succeed without paging
* [Might this be more than 4 MB?]
@@ -59,6 +61,13 @@ extern int hibernation_snapshot(int platform_mode);
extern int hibernation_restore(int platform_mode);
extern int hibernation_platform_enter(void);
+#ifdef CONFIG_DEBUG_RODATA
+/* kernel/power/snapshot.c */
+extern void enable_restore_image_protection(void);
+#else
+static inline void enable_restore_image_protection(void) {}
+#endif /* CONFIG_DEBUG_RODATA */
+
#else /* !CONFIG_HIBERNATION */
static inline void hibernate_reserved_size_init(void) {}
@@ -200,6 +209,8 @@ static inline void suspend_test_finish(const char *label) {}
#ifdef CONFIG_PM_SLEEP
/* kernel/power/main.c */
+extern int __pm_notifier_call_chain(unsigned long val, int nr_to_call,
+ int *nr_calls);
extern int pm_notifier_call_chain(unsigned long val);
#endif
diff --git a/kernel/power/process.c b/kernel/power/process.c
index 0c2ee9761d57..8f27d5a8adf6 100644
--- a/kernel/power/process.c
+++ b/kernel/power/process.c
@@ -89,6 +89,9 @@ static int try_to_freeze_tasks(bool user_only)
elapsed_msecs / 1000, elapsed_msecs % 1000,
todo - wq_busy, wq_busy);
+ if (wq_busy)
+ show_workqueue_state();
+
if (!wakeup) {
read_lock(&tasklist_lock);
for_each_process_thread(g, p) {
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 3a970604308f..d90df926b59f 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -38,6 +38,43 @@
#include "power.h"
+#ifdef CONFIG_DEBUG_RODATA
+static bool hibernate_restore_protection;
+static bool hibernate_restore_protection_active;
+
+void enable_restore_image_protection(void)
+{
+ hibernate_restore_protection = true;
+}
+
+static inline void hibernate_restore_protection_begin(void)
+{
+ hibernate_restore_protection_active = hibernate_restore_protection;
+}
+
+static inline void hibernate_restore_protection_end(void)
+{
+ hibernate_restore_protection_active = false;
+}
+
+static inline void hibernate_restore_protect_page(void *page_address)
+{
+ if (hibernate_restore_protection_active)
+ set_memory_ro((unsigned long)page_address, 1);
+}
+
+static inline void hibernate_restore_unprotect_page(void *page_address)
+{
+ if (hibernate_restore_protection_active)
+ set_memory_rw((unsigned long)page_address, 1);
+}
+#else
+static inline void hibernate_restore_protection_begin(void) {}
+static inline void hibernate_restore_protection_end(void) {}
+static inline void hibernate_restore_protect_page(void *page_address) {}
+static inline void hibernate_restore_unprotect_page(void *page_address) {}
+#endif /* CONFIG_DEBUG_RODATA */
+
static int swsusp_page_is_free(struct page *);
static void swsusp_set_page_forbidden(struct page *);
static void swsusp_unset_page_forbidden(struct page *);
@@ -67,25 +104,32 @@ void __init hibernate_image_size_init(void)
image_size = ((totalram_pages * 2) / 5) * PAGE_SIZE;
}
-/* List of PBEs needed for restoring the pages that were allocated before
+/*
+ * List of PBEs needed for restoring the pages that were allocated before
* the suspend and included in the suspend image, but have also been
* allocated by the "resume" kernel, so their contents cannot be written
* directly to their "original" page frames.
*/
struct pbe *restore_pblist;
-/* Pointer to an auxiliary buffer (1 page) */
-static void *buffer;
+/* struct linked_page is used to build chains of pages */
-/**
- * @safe_needed - on resume, for storing the PBE list and the image,
- * we can only use memory pages that do not conflict with the pages
- * used before suspend. The unsafe pages have PageNosaveFree set
- * and we count them using unsafe_pages.
- *
- * Each allocated image page is marked as PageNosave and PageNosaveFree
- * so that swsusp_free() can release it.
+#define LINKED_PAGE_DATA_SIZE (PAGE_SIZE - sizeof(void *))
+
+struct linked_page {
+ struct linked_page *next;
+ char data[LINKED_PAGE_DATA_SIZE];
+} __packed;
+
+/*
+ * List of "safe" pages (ie. pages that were not used by the image kernel
+ * before hibernation) that may be used as temporary storage for image kernel
+ * memory contents.
*/
+static struct linked_page *safe_pages_list;
+
+/* Pointer to an auxiliary buffer (1 page) */
+static void *buffer;
#define PG_ANY 0
#define PG_SAFE 1
@@ -94,6 +138,19 @@ static void *buffer;
static unsigned int allocated_unsafe_pages;
+/**
+ * get_image_page - Allocate a page for a hibernation image.
+ * @gfp_mask: GFP mask for the allocation.
+ * @safe_needed: Get pages that were not used before hibernation (restore only)
+ *
+ * During image restoration, for storing the PBE list and the image data, we can
+ * only use memory pages that do not conflict with the pages used before
+ * hibernation. The "unsafe" pages have PageNosaveFree set and we count them
+ * using allocated_unsafe_pages.
+ *
+ * Each allocated image page is marked as PageNosave and PageNosaveFree so that
+ * swsusp_free() can release it.
+ */
static void *get_image_page(gfp_t gfp_mask, int safe_needed)
{
void *res;
@@ -113,9 +170,21 @@ static void *get_image_page(gfp_t gfp_mask, int safe_needed)
return res;
}
+static void *__get_safe_page(gfp_t gfp_mask)
+{
+ if (safe_pages_list) {
+ void *ret = safe_pages_list;
+
+ safe_pages_list = safe_pages_list->next;
+ memset(ret, 0, PAGE_SIZE);
+ return ret;
+ }
+ return get_image_page(gfp_mask, PG_SAFE);
+}
+
unsigned long get_safe_page(gfp_t gfp_mask)
{
- return (unsigned long)get_image_page(gfp_mask, PG_SAFE);
+ return (unsigned long)__get_safe_page(gfp_mask);
}
static struct page *alloc_image_page(gfp_t gfp_mask)
@@ -130,11 +199,22 @@ static struct page *alloc_image_page(gfp_t gfp_mask)
return page;
}
+static void recycle_safe_page(void *page_address)
+{
+ struct linked_page *lp = page_address;
+
+ lp->next = safe_pages_list;
+ safe_pages_list = lp;
+}
+
/**
- * free_image_page - free page represented by @addr, allocated with
- * get_image_page (page flags set by it must be cleared)
+ * free_image_page - Free a page allocated for hibernation image.
+ * @addr: Address of the page to free.
+ * @clear_nosave_free: If set, clear the PageNosaveFree bit for the page.
+ *
+ * The page to free should have been allocated by get_image_page() (page flags
+ * set by it are affected).
*/
-
static inline void free_image_page(void *addr, int clear_nosave_free)
{
struct page *page;
@@ -150,17 +230,8 @@ static inline void free_image_page(void *addr, int clear_nosave_free)
__free_page(page);
}
-/* struct linked_page is used to build chains of pages */
-
-#define LINKED_PAGE_DATA_SIZE (PAGE_SIZE - sizeof(void *))
-
-struct linked_page {
- struct linked_page *next;
- char data[LINKED_PAGE_DATA_SIZE];
-} __packed;
-
-static inline void
-free_list_of_pages(struct linked_page *list, int clear_page_nosave)
+static inline void free_list_of_pages(struct linked_page *list,
+ int clear_page_nosave)
{
while (list) {
struct linked_page *lp = list->next;
@@ -170,30 +241,28 @@ free_list_of_pages(struct linked_page *list, int clear_page_nosave)
}
}
-/**
- * struct chain_allocator is used for allocating small objects out of
- * a linked list of pages called 'the chain'.
- *
- * The chain grows each time when there is no room for a new object in
- * the current page. The allocated objects cannot be freed individually.
- * It is only possible to free them all at once, by freeing the entire
- * chain.
- *
- * NOTE: The chain allocator may be inefficient if the allocated objects
- * are not much smaller than PAGE_SIZE.
- */
-
+/*
+ * struct chain_allocator is used for allocating small objects out of
+ * a linked list of pages called 'the chain'.
+ *
+ * The chain grows each time when there is no room for a new object in
+ * the current page. The allocated objects cannot be freed individually.
+ * It is only possible to free them all at once, by freeing the entire
+ * chain.
+ *
+ * NOTE: The chain allocator may be inefficient if the allocated objects
+ * are not much smaller than PAGE_SIZE.
+ */
struct chain_allocator {
struct linked_page *chain; /* the chain */
unsigned int used_space; /* total size of objects allocated out
- * of the current page
- */
+ of the current page */
gfp_t gfp_mask; /* mask for allocating pages */
int safe_needed; /* if set, only "safe" pages are allocated */
};
-static void
-chain_init(struct chain_allocator *ca, gfp_t gfp_mask, int safe_needed)
+static void chain_init(struct chain_allocator *ca, gfp_t gfp_mask,
+ int safe_needed)
{
ca->chain = NULL;
ca->used_space = LINKED_PAGE_DATA_SIZE;
@@ -208,7 +277,8 @@ static void *chain_alloc(struct chain_allocator *ca, unsigned int size)
if (LINKED_PAGE_DATA_SIZE - ca->used_space < size) {
struct linked_page *lp;
- lp = get_image_page(ca->gfp_mask, ca->safe_needed);
+ lp = ca->safe_needed ? __get_safe_page(ca->gfp_mask) :
+ get_image_page(ca->gfp_mask, PG_ANY);
if (!lp)
return NULL;
@@ -222,44 +292,44 @@ static void *chain_alloc(struct chain_allocator *ca, unsigned int size)
}
/**
- * Data types related to memory bitmaps.
+ * Data types related to memory bitmaps.
*
- * Memory bitmap is a structure consiting of many linked lists of
- * objects. The main list's elements are of type struct zone_bitmap
- * and each of them corresonds to one zone. For each zone bitmap
- * object there is a list of objects of type struct bm_block that
- * represent each blocks of bitmap in which information is stored.
+ * Memory bitmap is a structure consiting of many linked lists of
+ * objects. The main list's elements are of type struct zone_bitmap
+ * and each of them corresonds to one zone. For each zone bitmap
+ * object there is a list of objects of type struct bm_block that
+ * represent each blocks of bitmap in which information is stored.
*
- * struct memory_bitmap contains a pointer to the main list of zone
- * bitmap objects, a struct bm_position used for browsing the bitmap,
- * and a pointer to the list of pages used for allocating all of the
- * zone bitmap objects and bitmap block objects.
+ * struct memory_bitmap contains a pointer to the main list of zone
+ * bitmap objects, a struct bm_position used for browsing the bitmap,
+ * and a pointer to the list of pages used for allocating all of the
+ * zone bitmap objects and bitmap block objects.
*
- * NOTE: It has to be possible to lay out the bitmap in memory
- * using only allocations of order 0. Additionally, the bitmap is
- * designed to work with arbitrary number of zones (this is over the
- * top for now, but let's avoid making unnecessary assumptions ;-).
+ * NOTE: It has to be possible to lay out the bitmap in memory
+ * using only allocations of order 0. Additionally, the bitmap is
+ * designed to work with arbitrary number of zones (this is over the
+ * top for now, but let's avoid making unnecessary assumptions ;-).
*
- * struct zone_bitmap contains a pointer to a list of bitmap block
- * objects and a pointer to the bitmap block object that has been
- * most recently used for setting bits. Additionally, it contains the
- * pfns that correspond to the start and end of the represented zone.
+ * struct zone_bitmap contains a pointer to a list of bitmap block
+ * objects and a pointer to the bitmap block object that has been
+ * most recently used for setting bits. Additionally, it contains the
+ * PFNs that correspond to the start and end of the represented zone.
*
- * struct bm_block contains a pointer to the memory page in which
- * information is stored (in the form of a block of bitmap)
- * It also contains the pfns that correspond to the start and end of
- * the represented memory area.
+ * struct bm_block contains a pointer to the memory page in which
+ * information is stored (in the form of a block of bitmap)
+ * It also contains the pfns that correspond to the start and end of
+ * the represented memory area.
*
- * The memory bitmap is organized as a radix tree to guarantee fast random
- * access to the bits. There is one radix tree for each zone (as returned
- * from create_mem_extents).
+ * The memory bitmap is organized as a radix tree to guarantee fast random
+ * access to the bits. There is one radix tree for each zone (as returned
+ * from create_mem_extents).
*
- * One radix tree is represented by one struct mem_zone_bm_rtree. There are
- * two linked lists for the nodes of the tree, one for the inner nodes and
- * one for the leave nodes. The linked leave nodes are used for fast linear
- * access of the memory bitmap.
+ * One radix tree is represented by one struct mem_zone_bm_rtree. There are
+ * two linked lists for the nodes of the tree, one for the inner nodes and
+ * one for the leave nodes. The linked leave nodes are used for fast linear
+ * access of the memory bitmap.
*
- * The struct rtree_node represents one node of the radix tree.
+ * The struct rtree_node represents one node of the radix tree.
*/
#define BM_END_OF_MAP (~0UL)
@@ -305,9 +375,8 @@ struct bm_position {
struct memory_bitmap {
struct list_head zones;
struct linked_page *p_list; /* list of pages used to store zone
- * bitmap objects and bitmap block
- * objects
- */
+ bitmap objects and bitmap block
+ objects */
struct bm_position cur; /* most recently used bit position */
};
@@ -321,12 +390,12 @@ struct memory_bitmap {
#endif
#define BM_RTREE_LEVEL_MASK ((1UL << BM_RTREE_LEVEL_SHIFT) - 1)
-/*
- * alloc_rtree_node - Allocate a new node and add it to the radix tree.
+/**
+ * alloc_rtree_node - Allocate a new node and add it to the radix tree.
*
- * This function is used to allocate inner nodes as well as the
- * leave nodes of the radix tree. It also adds the node to the
- * corresponding linked list passed in by the *list parameter.
+ * This function is used to allocate inner nodes as well as the
+ * leave nodes of the radix tree. It also adds the node to the
+ * corresponding linked list passed in by the *list parameter.
*/
static struct rtree_node *alloc_rtree_node(gfp_t gfp_mask, int safe_needed,
struct chain_allocator *ca,
@@ -347,12 +416,12 @@ static struct rtree_node *alloc_rtree_node(gfp_t gfp_mask, int safe_needed,
return node;
}
-/*
- * add_rtree_block - Add a new leave node to the radix tree
+/**
+ * add_rtree_block - Add a new leave node to the radix tree.
*
- * The leave nodes need to be allocated in order to keep the leaves
- * linked list in order. This is guaranteed by the zone->blocks
- * counter.
+ * The leave nodes need to be allocated in order to keep the leaves
+ * linked list in order. This is guaranteed by the zone->blocks
+ * counter.
*/
static int add_rtree_block(struct mem_zone_bm_rtree *zone, gfp_t gfp_mask,
int safe_needed, struct chain_allocator *ca)
@@ -417,17 +486,18 @@ static int add_rtree_block(struct mem_zone_bm_rtree *zone, gfp_t gfp_mask,
static void free_zone_bm_rtree(struct mem_zone_bm_rtree *zone,
int clear_nosave_free);
-/*
- * create_zone_bm_rtree - create a radix tree for one zone
+/**
+ * create_zone_bm_rtree - Create a radix tree for one zone.
*
- * Allocated the mem_zone_bm_rtree structure and initializes it.
- * This function also allocated and builds the radix tree for the
- * zone.
+ * Allocated the mem_zone_bm_rtree structure and initializes it.
+ * This function also allocated and builds the radix tree for the
+ * zone.
*/
-static struct mem_zone_bm_rtree *
-create_zone_bm_rtree(gfp_t gfp_mask, int safe_needed,
- struct chain_allocator *ca,
- unsigned long start, unsigned long end)
+static struct mem_zone_bm_rtree *create_zone_bm_rtree(gfp_t gfp_mask,
+ int safe_needed,
+ struct chain_allocator *ca,
+ unsigned long start,
+ unsigned long end)
{
struct mem_zone_bm_rtree *zone;
unsigned int i, nr_blocks;
@@ -454,12 +524,12 @@ create_zone_bm_rtree(gfp_t gfp_mask, int safe_needed,
return zone;
}
-/*
- * free_zone_bm_rtree - Free the memory of the radix tree
+/**
+ * free_zone_bm_rtree - Free the memory of the radix tree.
*
- * Free all node pages of the radix tree. The mem_zone_bm_rtree
- * structure itself is not freed here nor are the rtree_node
- * structs.
+ * Free all node pages of the radix tree. The mem_zone_bm_rtree
+ * structure itself is not freed here nor are the rtree_node
+ * structs.
*/
static void free_zone_bm_rtree(struct mem_zone_bm_rtree *zone,
int clear_nosave_free)
@@ -492,8 +562,8 @@ struct mem_extent {
};
/**
- * free_mem_extents - free a list of memory extents
- * @list - list of extents to empty
+ * free_mem_extents - Free a list of memory extents.
+ * @list: List of extents to free.
*/
static void free_mem_extents(struct list_head *list)
{
@@ -506,10 +576,11 @@ static void free_mem_extents(struct list_head *list)
}
/**
- * create_mem_extents - create a list of memory extents representing
- * contiguous ranges of PFNs
- * @list - list to put the extents into
- * @gfp_mask - mask to use for memory allocations
+ * create_mem_extents - Create a list of memory extents.
+ * @list: List to put the extents into.
+ * @gfp_mask: Mask to use for memory allocations.
+ *
+ * The extents represent contiguous ranges of PFNs.
*/
static int create_mem_extents(struct list_head *list, gfp_t gfp_mask)
{
@@ -565,10 +636,10 @@ static int create_mem_extents(struct list_head *list, gfp_t gfp_mask)
}
/**
- * memory_bm_create - allocate memory for a memory bitmap
- */
-static int
-memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask, int safe_needed)
+ * memory_bm_create - Allocate memory for a memory bitmap.
+ */
+static int memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask,
+ int safe_needed)
{
struct chain_allocator ca;
struct list_head mem_extents;
@@ -607,8 +678,9 @@ memory_bm_create(struct memory_bitmap *bm, gfp_t gfp_mask, int safe_needed)
}
/**
- * memory_bm_free - free memory occupied by the memory bitmap @bm
- */
+ * memory_bm_free - Free memory occupied by the memory bitmap.
+ * @bm: Memory bitmap.
+ */
static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free)
{
struct mem_zone_bm_rtree *zone;
@@ -622,14 +694,13 @@ static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free)
}
/**
- * memory_bm_find_bit - Find the bit for pfn in the memory
- * bitmap
+ * memory_bm_find_bit - Find the bit for a given PFN in a memory bitmap.
*
- * Find the bit in the bitmap @bm that corresponds to given pfn.
- * The cur.zone, cur.block and cur.node_pfn member of @bm are
- * updated.
- * It walks the radix tree to find the page which contains the bit for
- * pfn and returns the bit position in **addr and *bit_nr.
+ * Find the bit in memory bitmap @bm that corresponds to the given PFN.
+ * The cur.zone, cur.block and cur.node_pfn members of @bm are updated.
+ *
+ * Walk the radix tree to find the page containing the bit that represents @pfn
+ * and return the position of the bit in @addr and @bit_nr.
*/
static int memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
void **addr, unsigned int *bit_nr)
@@ -658,10 +729,9 @@ static int memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
zone_found:
/*
- * We have a zone. Now walk the radix tree to find the leave
- * node for our pfn.
+ * We have found the zone. Now walk the radix tree to find the leaf node
+ * for our PFN.
*/
-
node = bm->cur.node;
if (((pfn - zone->start_pfn) & ~BM_BLOCK_MASK) == bm->cur.node_pfn)
goto node_found;
@@ -754,14 +824,14 @@ static bool memory_bm_pfn_present(struct memory_bitmap *bm, unsigned long pfn)
}
/*
- * rtree_next_node - Jumps to the next leave node
+ * rtree_next_node - Jump to the next leaf node.
*
- * Sets the position to the beginning of the next node in the
- * memory bitmap. This is either the next node in the current
- * zone's radix tree or the first node in the radix tree of the
- * next zone.
+ * Set the position to the beginning of the next node