* [PATCH 1/3] swsusp: Fix mark_free_pages
2006-08-02 16:42 [PATCH 0/3] swsusp cleanups Rafael J. Wysocki
@ 2006-08-02 16:48 ` Rafael J. Wysocki
2006-08-02 19:51 ` Dave Hansen
2006-08-02 16:53 ` [PATCH 2/3] swsusp: Reorder memory-allocating functions Rafael J. Wysocki
2006-08-02 16:57 ` [PATCH 3/3] swsusp: Fix alloc_pagedir Rafael J. Wysocki
2 siblings, 1 reply; 10+ messages in thread
From: Rafael J. Wysocki @ 2006-08-02 16:48 UTC (permalink / raw)
To: Andrew Morton; +Cc: LKML, Pavel Machek
Clean up mm/page_alloc.c#mark_free_pages() and make it avoid clearing
PageNosaveFree for PageNosave pages. This allows us to get rid of an ugly
hack in kernel/power/snapshot.c#copy_data_pages().
Additionally, the page-copying loop in copy_data_pages() is moved to an
inline function.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
kernel/power/snapshot.c | 27 +++++++++++++--------------
mm/page_alloc.c | 22 ++++++++++++++--------
2 files changed, 27 insertions(+), 22 deletions(-)
Index: linux-2.6.18-rc2-mm1/mm/page_alloc.c
===================================================================
--- linux-2.6.18-rc2-mm1.orig/mm/page_alloc.c 2006-07-31 20:42:29.000000000 +0200
+++ linux-2.6.18-rc2-mm1/mm/page_alloc.c 2006-07-31 20:52:11.000000000 +0200
@@ -703,7 +703,8 @@ static void __drain_pages(unsigned int c
void mark_free_pages(struct zone *zone)
{
- unsigned long zone_pfn, flags;
+ unsigned long pfn, max_zone_pfn;
+ unsigned long flags;
int order;
struct list_head *curr;
@@ -711,18 +712,23 @@ void mark_free_pages(struct zone *zone)
return;
spin_lock_irqsave(&zone->lock, flags);
- for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn)
- ClearPageNosaveFree(pfn_to_page(zone_pfn + zone->zone_start_pfn));
+ max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
+ for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) {
+ struct page *page = pfn_to_page(pfn);
+
+ if (!PageNosave(page))
+ ClearPageNosaveFree(page);
+ }
for (order = MAX_ORDER - 1; order >= 0; --order)
list_for_each(curr, &zone->free_area[order].free_list) {
- unsigned long start_pfn, i;
+ unsigned long i;
- start_pfn = page_to_pfn(list_entry(curr, struct page, lru));
+ pfn = page_to_pfn(list_entry(curr, struct page, lru));
+ for (i = 0; i < (1UL << order); i++)
+ SetPageNosaveFree(pfn_to_page(pfn + i));
+ }
- for (i=0; i < (1<<order); i++)
- SetPageNosaveFree(pfn_to_page(start_pfn+i));
- }
spin_unlock_irqrestore(&zone->lock, flags);
}
Index: linux-2.6.18-rc2-mm1/kernel/power/snapshot.c
===================================================================
--- linux-2.6.18-rc2-mm1.orig/kernel/power/snapshot.c 2006-07-31 20:47:26.000000000 +0200
+++ linux-2.6.18-rc2-mm1/kernel/power/snapshot.c 2006-07-31 21:01:22.000000000 +0200
@@ -208,37 +208,36 @@ unsigned int count_data_pages(void)
return n;
}
+static inline void copy_data_page(long *dst, long *src)
+{
+ int n;
+
+ /* copy_page and memcpy are not usable for copying task structs. */
+ for (n = PAGE_SIZE / sizeof(long); n; n--)
+ *dst++ = *src++;
+}
+
static void copy_data_pages(struct pbe *pblist)
{
struct zone *zone;
unsigned long pfn, max_zone_pfn;
- struct pbe *pbe, *p;
+ struct pbe *pbe;
pbe = pblist;
for_each_zone (zone) {
if (is_highmem(zone))
continue;
mark_free_pages(zone);
- /* This is necessary for swsusp_free() */
- for_each_pb_page (p, pblist)
- SetPageNosaveFree(virt_to_page(p));
- for_each_pbe (p, pblist)
- SetPageNosaveFree(virt_to_page(p->address));
max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) {
struct page *page = saveable_page(pfn);
if (page) {
- long *src, *dst;
- int n;
+ void *ptr = page_address(page);;
BUG_ON(!pbe);
- pbe->orig_address = (unsigned long)page_address(page);
- /* copy_page and memcpy are not usable for copying task structs. */
- dst = (long *)pbe->address;
- src = (long *)pbe->orig_address;
- for (n = PAGE_SIZE / sizeof(long); n; n--)
- *dst++ = *src++;
+ copy_data_page((void *)pbe->address, ptr);
+ pbe->orig_address = (unsigned long)ptr;
pbe = pbe->next;
}
}
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH 1/3] swsusp: Fix mark_free_pages
2006-08-02 16:48 ` [PATCH 1/3] swsusp: Fix mark_free_pages Rafael J. Wysocki
@ 2006-08-02 19:51 ` Dave Hansen
2006-08-02 20:12 ` Rafael J. Wysocki
0 siblings, 1 reply; 10+ messages in thread
From: Dave Hansen @ 2006-08-02 19:51 UTC (permalink / raw)
To: Rafael J. Wysocki; +Cc: Andrew Morton, LKML, Pavel Machek
On Wed, 2006-08-02 at 18:48 +0200, Rafael J. Wysocki wrote:
> + max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
> + for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) {
> + struct page *page = pfn_to_page(pfn);
> +
> + if (!PageNosave(page))
> + ClearPageNosaveFree(page);
> + }
This is certainly not the only place in swsusp where there is a bug like
this, but it is not correct to assume that each page inside of a zone is
valid. With sparsemem, you need to do pfn_valid() on each pfn before
calling pfn_to_page().
Something like:
max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) {
struct page *page;
if (!pfn_valid(pfn))
continue;
page = pfn_to_page(pfn);
if (!PageNosave(page))
ClearPageNosaveFree(page);
}
-- Dave
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH 1/3] swsusp: Fix mark_free_pages
2006-08-02 19:51 ` Dave Hansen
@ 2006-08-02 20:12 ` Rafael J. Wysocki
2006-08-02 20:30 ` Pavel Machek
0 siblings, 1 reply; 10+ messages in thread
From: Rafael J. Wysocki @ 2006-08-02 20:12 UTC (permalink / raw)
To: Dave Hansen; +Cc: Andrew Morton, LKML, Pavel Machek
On Wednesday 02 August 2006 21:51, Dave Hansen wrote:
> On Wed, 2006-08-02 at 18:48 +0200, Rafael J. Wysocki wrote:
> > + max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
> > + for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) {
> > + struct page *page = pfn_to_page(pfn);
> > +
> > + if (!PageNosave(page))
> > + ClearPageNosaveFree(page);
> > + }
>
> This is certainly not the only place in swsusp where there is a bug like
> this,
Well, I don't think so. They have been hunted for and dealt whith, except
for this one. ;-)
> but it is not correct to assume that each page inside of a zone is
> valid.
Obviously, I just forgot about it.
---
Clean up mm/page_alloc.c#mark_free_pages() and make it avoid clearing
PageNosaveFree for PageNosave pages. This allows us to get rid of an ugly
hack in kernel/power/snapshot.c#copy_data_pages().
Additionally, the page-copying loop in copy_data_pages() is moved to an
inline function.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
kernel/power/snapshot.c | 27 +++++++++++++--------------
mm/page_alloc.c | 24 ++++++++++++++++--------
2 files changed, 29 insertions(+), 22 deletions(-)
Index: linux-2.6.18-rc2-mm1/mm/page_alloc.c
===================================================================
--- linux-2.6.18-rc2-mm1.orig/mm/page_alloc.c
+++ linux-2.6.18-rc2-mm1/mm/page_alloc.c
@@ -703,7 +703,8 @@ static void __drain_pages(unsigned int c
void mark_free_pages(struct zone *zone)
{
- unsigned long zone_pfn, flags;
+ unsigned long pfn, max_zone_pfn;
+ unsigned long flags;
int order;
struct list_head *curr;
@@ -711,18 +712,25 @@ void mark_free_pages(struct zone *zone)
return;
spin_lock_irqsave(&zone->lock, flags);
- for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn)
- ClearPageNosaveFree(pfn_to_page(zone_pfn + zone->zone_start_pfn));
+
+ max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
+ for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
+ if (pfn_valid(pfn)) {
+ struct page *page = pfn_to_page(pfn);
+
+ if (!PageNosave(page))
+ ClearPageNosaveFree(page);
+ }
for (order = MAX_ORDER - 1; order >= 0; --order)
list_for_each(curr, &zone->free_area[order].free_list) {
- unsigned long start_pfn, i;
+ unsigned long i;
- start_pfn = page_to_pfn(list_entry(curr, struct page, lru));
+ pfn = page_to_pfn(list_entry(curr, struct page, lru));
+ for (i = 0; i < (1UL << order); i++)
+ SetPageNosaveFree(pfn_to_page(pfn + i));
+ }
- for (i=0; i < (1<<order); i++)
- SetPageNosaveFree(pfn_to_page(start_pfn+i));
- }
spin_unlock_irqrestore(&zone->lock, flags);
}
Index: linux-2.6.18-rc2-mm1/kernel/power/snapshot.c
===================================================================
--- linux-2.6.18-rc2-mm1.orig/kernel/power/snapshot.c
+++ linux-2.6.18-rc2-mm1/kernel/power/snapshot.c
@@ -208,37 +208,36 @@ unsigned int count_data_pages(void)
return n;
}
+static inline void copy_data_page(long *dst, long *src)
+{
+ int n;
+
+ /* copy_page and memcpy are not usable for copying task structs. */
+ for (n = PAGE_SIZE / sizeof(long); n; n--)
+ *dst++ = *src++;
+}
+
static void copy_data_pages(struct pbe *pblist)
{
struct zone *zone;
unsigned long pfn, max_zone_pfn;
- struct pbe *pbe, *p;
+ struct pbe *pbe;
pbe = pblist;
for_each_zone (zone) {
if (is_highmem(zone))
continue;
mark_free_pages(zone);
- /* This is necessary for swsusp_free() */
- for_each_pb_page (p, pblist)
- SetPageNosaveFree(virt_to_page(p));
- for_each_pbe (p, pblist)
- SetPageNosaveFree(virt_to_page(p->address));
max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) {
struct page *page = saveable_page(pfn);
if (page) {
- long *src, *dst;
- int n;
+ void *ptr = page_address(page);;
BUG_ON(!pbe);
- pbe->orig_address = (unsigned long)page_address(page);
- /* copy_page and memcpy are not usable for copying task structs. */
- dst = (long *)pbe->address;
- src = (long *)pbe->orig_address;
- for (n = PAGE_SIZE / sizeof(long); n; n--)
- *dst++ = *src++;
+ copy_data_page((void *)pbe->address, ptr);
+ pbe->orig_address = (unsigned long)ptr;
pbe = pbe->next;
}
}
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH 1/3] swsusp: Fix mark_free_pages
2006-08-02 20:12 ` Rafael J. Wysocki
@ 2006-08-02 20:30 ` Pavel Machek
2006-08-02 20:48 ` Rafael J. Wysocki
0 siblings, 1 reply; 10+ messages in thread
From: Pavel Machek @ 2006-08-02 20:30 UTC (permalink / raw)
To: Rafael J. Wysocki; +Cc: Dave Hansen, Andrew Morton, LKML
Hi!
Looks good to me (ACK).
> if (page) {
> - long *src, *dst;
> - int n;
> + void *ptr = page_address(page);;
You probably want to remove one of ";"s.
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH 1/3] swsusp: Fix mark_free_pages
2006-08-02 20:30 ` Pavel Machek
@ 2006-08-02 20:48 ` Rafael J. Wysocki
0 siblings, 0 replies; 10+ messages in thread
From: Rafael J. Wysocki @ 2006-08-02 20:48 UTC (permalink / raw)
To: Pavel Machek; +Cc: Dave Hansen, Andrew Morton, LKML
On Wednesday 02 August 2006 22:30, Pavel Machek wrote:
> Hi!
>
> Looks good to me (ACK).
>
> > if (page) {
> > - long *src, *dst;
> > - int n;
> > + void *ptr = page_address(page);;
>
> You probably want to remove one of ";"s.
Ouch.
I hope this is the final one.
---
Clean up mm/page_alloc.c#mark_free_pages() and make it avoid clearing
PageNosaveFree for PageNosave pages. This allows us to get rid of an ugly
hack in kernel/power/snapshot.c#copy_data_pages().
Additionally, the page-copying loop in copy_data_pages() is moved to an
inline function.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
kernel/power/snapshot.c | 27 +++++++++++++--------------
mm/page_alloc.c | 24 ++++++++++++++++--------
2 files changed, 29 insertions(+), 22 deletions(-)
Index: linux-2.6.18-rc2-mm1/mm/page_alloc.c
===================================================================
--- linux-2.6.18-rc2-mm1.orig/mm/page_alloc.c
+++ linux-2.6.18-rc2-mm1/mm/page_alloc.c
@@ -703,7 +703,8 @@ static void __drain_pages(unsigned int c
void mark_free_pages(struct zone *zone)
{
- unsigned long zone_pfn, flags;
+ unsigned long pfn, max_zone_pfn;
+ unsigned long flags;
int order;
struct list_head *curr;
@@ -711,18 +712,25 @@ void mark_free_pages(struct zone *zone)
return;
spin_lock_irqsave(&zone->lock, flags);
- for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn)
- ClearPageNosaveFree(pfn_to_page(zone_pfn + zone->zone_start_pfn));
+
+ max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
+ for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
+ if (pfn_valid(pfn)) {
+ struct page *page = pfn_to_page(pfn);
+
+ if (!PageNosave(page))
+ ClearPageNosaveFree(page);
+ }
for (order = MAX_ORDER - 1; order >= 0; --order)
list_for_each(curr, &zone->free_area[order].free_list) {
- unsigned long start_pfn, i;
+ unsigned long i;
- start_pfn = page_to_pfn(list_entry(curr, struct page, lru));
+ pfn = page_to_pfn(list_entry(curr, struct page, lru));
+ for (i = 0; i < (1UL << order); i++)
+ SetPageNosaveFree(pfn_to_page(pfn + i));
+ }
- for (i=0; i < (1<<order); i++)
- SetPageNosaveFree(pfn_to_page(start_pfn+i));
- }
spin_unlock_irqrestore(&zone->lock, flags);
}
Index: linux-2.6.18-rc2-mm1/kernel/power/snapshot.c
===================================================================
--- linux-2.6.18-rc2-mm1.orig/kernel/power/snapshot.c
+++ linux-2.6.18-rc2-mm1/kernel/power/snapshot.c
@@ -208,37 +208,36 @@ unsigned int count_data_pages(void)
return n;
}
+static inline void copy_data_page(long *dst, long *src)
+{
+ int n;
+
+ /* copy_page and memcpy are not usable for copying task structs. */
+ for (n = PAGE_SIZE / sizeof(long); n; n--)
+ *dst++ = *src++;
+}
+
static void copy_data_pages(struct pbe *pblist)
{
struct zone *zone;
unsigned long pfn, max_zone_pfn;
- struct pbe *pbe, *p;
+ struct pbe *pbe;
pbe = pblist;
for_each_zone (zone) {
if (is_highmem(zone))
continue;
mark_free_pages(zone);
- /* This is necessary for swsusp_free() */
- for_each_pb_page (p, pblist)
- SetPageNosaveFree(virt_to_page(p));
- for_each_pbe (p, pblist)
- SetPageNosaveFree(virt_to_page(p->address));
max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) {
struct page *page = saveable_page(pfn);
if (page) {
- long *src, *dst;
- int n;
+ void *ptr = page_address(page);
BUG_ON(!pbe);
- pbe->orig_address = (unsigned long)page_address(page);
- /* copy_page and memcpy are not usable for copying task structs. */
- dst = (long *)pbe->address;
- src = (long *)pbe->orig_address;
- for (n = PAGE_SIZE / sizeof(long); n; n--)
- *dst++ = *src++;
+ copy_data_page((void *)pbe->address, ptr);
+ pbe->orig_address = (unsigned long)ptr;
pbe = pbe->next;
}
}
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCH 2/3] swsusp: Reorder memory-allocating functions
2006-08-02 16:42 [PATCH 0/3] swsusp cleanups Rafael J. Wysocki
2006-08-02 16:48 ` [PATCH 1/3] swsusp: Fix mark_free_pages Rafael J. Wysocki
@ 2006-08-02 16:53 ` Rafael J. Wysocki
2006-08-02 20:19 ` Pavel Machek
2006-08-02 16:57 ` [PATCH 3/3] swsusp: Fix alloc_pagedir Rafael J. Wysocki
2 siblings, 1 reply; 10+ messages in thread
From: Rafael J. Wysocki @ 2006-08-02 16:53 UTC (permalink / raw)
To: Andrew Morton; +Cc: LKML, Pavel Machek
Move some functions in kernel/power/snapshot.c to a better place
(in the same file) and introduce free_image_page() (will be necessary in the
future).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
kernel/power/snapshot.c | 93 +++++++++++++++++++++++++++---------------------
1 file changed, 53 insertions(+), 40 deletions(-)
Index: linux-2.6.18-rc2-mm1/kernel/power/snapshot.c
===================================================================
--- linux-2.6.18-rc2-mm1.orig/kernel/power/snapshot.c 2006-08-01 08:58:45.000000000 +0200
+++ linux-2.6.18-rc2-mm1/kernel/power/snapshot.c 2006-08-01 22:15:41.000000000 +0200
@@ -156,6 +156,58 @@ static inline int save_highmem(void) {re
static inline int restore_highmem(void) {return 0;}
#endif
+/**
+ * @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 are marked with the PG_nosave_free flag
+ * and we count them using unsafe_pages
+ */
+
+static unsigned int unsafe_pages;
+
+static void *alloc_image_page(gfp_t gfp_mask, int safe_needed)
+{
+ void *res;
+
+ res = (void *)get_zeroed_page(gfp_mask);
+ if (safe_needed)
+ while (res && PageNosaveFree(virt_to_page(res))) {
+ /* The page is unsafe, mark it for swsusp_free() */
+ SetPageNosave(virt_to_page(res));
+ unsafe_pages++;
+ res = (void *)get_zeroed_page(gfp_mask);
+ }
+ if (res) {
+ SetPageNosave(virt_to_page(res));
+ SetPageNosaveFree(virt_to_page(res));
+ }
+ return res;
+}
+
+unsigned long get_safe_page(gfp_t gfp_mask)
+{
+ return (unsigned long)alloc_image_page(gfp_mask, 1);
+}
+
+/**
+ * free_image_page - free page represented by @addr, allocated with
+ * alloc_image_page (page flags set by it must be cleared)
+ */
+
+static inline void free_image_page(void *addr, int clear_nosave_free)
+{
+ ClearPageNosave(virt_to_page(addr));
+ if (clear_nosave_free)
+ ClearPageNosaveFree(virt_to_page(addr));
+ free_page((unsigned long)addr);
+}
+
+/**
+ * pfn_is_nosave - check if given pfn is in the 'nosave' section
+ */
+
static inline int pfn_is_nosave(unsigned long pfn)
{
unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT;
@@ -245,7 +297,6 @@ static void copy_data_pages(struct pbe *
BUG_ON(pbe);
}
-
/**
* free_pagedir - free pages allocated with alloc_pagedir()
*/
@@ -256,10 +307,7 @@ static void free_pagedir(struct pbe *pbl
while (pblist) {
pbe = (pblist + PB_PAGE_SKIP)->next;
- ClearPageNosave(virt_to_page(pblist));
- if (clear_nosave_free)
- ClearPageNosaveFree(virt_to_page(pblist));
- free_page((unsigned long)pblist);
+ free_image_page(pblist, clear_nosave_free);
pblist = pbe;
}
}
@@ -303,41 +351,6 @@ static inline void create_pbe_list(struc
}
}
-static unsigned int unsafe_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 are marked with the PG_nosave_free flag
- * and we count them using unsafe_pages
- */
-
-static void *alloc_image_page(gfp_t gfp_mask, int safe_needed)
-{
- void *res;
-
- res = (void *)get_zeroed_page(gfp_mask);
- if (safe_needed)
- while (res && PageNosaveFree(virt_to_page(res))) {
- /* The page is unsafe, mark it for swsusp_free() */
- SetPageNosave(virt_to_page(res));
- unsafe_pages++;
- res = (void *)get_zeroed_page(gfp_mask);
- }
- if (res) {
- SetPageNosave(virt_to_page(res));
- SetPageNosaveFree(virt_to_page(res));
- }
- return res;
-}
-
-unsigned long get_safe_page(gfp_t gfp_mask)
-{
- return (unsigned long)alloc_image_page(gfp_mask, 1);
-}
-
/**
* alloc_pagedir - Allocate the page directory.
*
^ permalink raw reply [flat|nested] 10+ messages in thread* [PATCH 3/3] swsusp: Fix alloc_pagedir
2006-08-02 16:42 [PATCH 0/3] swsusp cleanups Rafael J. Wysocki
2006-08-02 16:48 ` [PATCH 1/3] swsusp: Fix mark_free_pages Rafael J. Wysocki
2006-08-02 16:53 ` [PATCH 2/3] swsusp: Reorder memory-allocating functions Rafael J. Wysocki
@ 2006-08-02 16:57 ` Rafael J. Wysocki
2006-08-02 20:22 ` Pavel Machek
2 siblings, 1 reply; 10+ messages in thread
From: Rafael J. Wysocki @ 2006-08-02 16:57 UTC (permalink / raw)
To: Andrew Morton; +Cc: LKML, Pavel Machek
Get rid of the FIXME in kernel/power/snapshot.c#alloc_pagedir() and
simplify the functions called by it.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
kernel/power/snapshot.c | 32 +++++++++++++++++---------------
1 file changed, 17 insertions(+), 15 deletions(-)
Index: linux-2.6.18-rc2-mm1/kernel/power/snapshot.c
===================================================================
--- linux-2.6.18-rc2-mm1.orig/kernel/power/snapshot.c 2006-08-01 22:15:41.000000000 +0200
+++ linux-2.6.18-rc2-mm1/kernel/power/snapshot.c 2006-08-01 22:24:57.000000000 +0200
@@ -316,12 +316,12 @@ static void free_pagedir(struct pbe *pbl
* fill_pb_page - Create a list of PBEs on a given memory page
*/
-static inline void fill_pb_page(struct pbe *pbpage)
+static inline void fill_pb_page(struct pbe *pbpage, unsigned int n)
{
struct pbe *p;
p = pbpage;
- pbpage += PB_PAGE_SKIP;
+ pbpage += n - 1;
do
p->next = p + 1;
while (++p < pbpage);
@@ -330,24 +330,26 @@ static inline void fill_pb_page(struct p
/**
* create_pbe_list - Create a list of PBEs on top of a given chain
* of memory pages allocated with alloc_pagedir()
+ *
+ * This function assumes that pages allocated by alloc_image_page() will
+ * always be zeroed.
*/
static inline void create_pbe_list(struct pbe *pblist, unsigned int nr_pages)
{
- struct pbe *pbpage, *p;
+ struct pbe *pbpage;
unsigned int num = PBES_PER_PAGE;
for_each_pb_page (pbpage, pblist) {
if (num >= nr_pages)
break;
- fill_pb_page(pbpage);
+ fill_pb_page(pbpage, PBES_PER_PAGE);
num += PBES_PER_PAGE;
}
if (pbpage) {
- for (num -= PBES_PER_PAGE - 1, p = pbpage; num < nr_pages; p++, num++)
- p->next = p + 1;
- p->next = NULL;
+ num -= PBES_PER_PAGE;
+ fill_pb_page(pbpage, nr_pages - num);
}
}
@@ -374,17 +376,17 @@ static struct pbe *alloc_pagedir(unsigne
return NULL;
pblist = alloc_image_page(gfp_mask, safe_needed);
- /* FIXME: rewrite this ugly loop */
- for (pbe = pblist, num = PBES_PER_PAGE; pbe && num < nr_pages;
- pbe = pbe->next, num += PBES_PER_PAGE) {
+ pbe = pblist;
+ for (num = PBES_PER_PAGE; num < nr_pages; num += PBES_PER_PAGE) {
+ if (!pbe) {
+ free_pagedir(pblist, 1);
+ return NULL;
+ }
pbe += PB_PAGE_SKIP;
pbe->next = alloc_image_page(gfp_mask, safe_needed);
+ pbe = pbe->next;
}
- if (!pbe) { /* get_zeroed_page() failed */
- free_pagedir(pblist, 1);
- pblist = NULL;
- } else
- create_pbe_list(pblist, nr_pages);
+ create_pbe_list(pblist, nr_pages);
return pblist;
}
^ permalink raw reply [flat|nested] 10+ messages in thread