diff --git a/include/linux/page-isolation.h b/include/linux/page-isolation.h
index 4eb26d2780460a6a821f110ce903ad2a1a54ccce..280ae96dc4c300d29418ececeb5e9b91acf27e2e 100644
--- a/include/linux/page-isolation.h
+++ b/include/linux/page-isolation.h
@@ -41,16 +41,6 @@ int move_freepages_block(struct zone *zone, struct page *page,
/*
* Changes migrate type in [start_pfn, end_pfn) to be MIGRATE_ISOLATE.
- * If specified range includes migrate types other than MOVABLE or CMA,
- * this will fail with -EBUSY.
- *
- * For isolating all pages in the range finally, the caller have to
- * free all pages in the range. test_page_isolated() can be used for
- * test it.
- *
- * The following flags are allowed (they can be combined in a bit mask)
- * SKIP_HWPOISON - ignore hwpoison pages
- * REPORT_FAILURE - report details about the failure to isolate the range
*/
int
start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index f767582af4f8c0f28102f2d77d8dc6a667ec3df5..0e0a16021fd5b6b230b11720d1d62e9d464f62e6 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1576,7 +1576,7 @@ static int __ref __offline_pages(unsigned long start_pfn,
{
unsigned long pfn, nr_pages;
long offlined_pages;
- int ret, node;
+ int ret, node, nr_isolate_pageblock;
unsigned long flags;
unsigned long valid_start, valid_end;
struct zone *zone;
@@ -1602,10 +1602,11 @@ static int __ref __offline_pages(unsigned long start_pfn,
ret = start_isolate_page_range(start_pfn, end_pfn,
MIGRATE_MOVABLE,
SKIP_HWPOISON | REPORT_FAILURE);
- if (ret) {
+ if (ret < 0) {
reason = "failure to isolate range";
goto failed_removal;
}
+ nr_isolate_pageblock = ret;
arg.start_pfn = start_pfn;
arg.nr_pages = nr_pages;
@@ -1657,8 +1658,16 @@ static int __ref __offline_pages(unsigned long start_pfn,
/* Ok, all of our target is isolated.
We cannot do rollback at this point. */
offline_isolated_pages(start_pfn, end_pfn);
- /* reset pagetype flags and makes migrate type to be MOVABLE */
- undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE);
+
+ /*
+ * Onlining will reset pagetype flags and makes migrate type
+ * MOVABLE, so just need to decrease the number of isolated
+ * pageblocks zone counter here.
+ */
+ spin_lock_irqsave(&zone->lock, flags);
+ zone->nr_isolate_pageblock -= nr_isolate_pageblock;
+ spin_unlock_irqrestore(&zone->lock, flags);
+
/* removal success */
adjust_managed_page_count(pfn_to_page(start_pfn), -offlined_pages);
zone->present_pages -= offlined_pages;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 03fcf73d47dabde0987f3542c3c87fca33bf5a5d..d96ca5bc555bbc432e135c876151e0699ee88162 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8233,7 +8233,7 @@ int alloc_contig_range(unsigned long start, unsigned long end,
ret = start_isolate_page_range(pfn_max_align_down(start),
pfn_max_align_up(end), migratetype, 0);
- if (ret)
+ if (ret < 0)
return ret;
/*
diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index ce323e56b34d6bc43a9e16cc9054f35290bb0b63..bf4159d771c79b8e4ded0b3f9df960e1ac24c433 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -160,27 +160,36 @@ __first_valid_page(unsigned long pfn, unsigned long nr_pages)
return NULL;
}
-/*
- * start_isolate_page_range() -- make page-allocation-type of range of pages
- * to be MIGRATE_ISOLATE.
- * @start_pfn: The lower PFN of the range to be isolated.
- * @end_pfn: The upper PFN of the range to be isolated.
- * @migratetype: migrate type to set in error recovery.
+/**
+ * start_isolate_page_range() - make page-allocation-type of range of pages to
+ * be MIGRATE_ISOLATE.
+ * @start_pfn: The lower PFN of the range to be isolated.
+ * @end_pfn: The upper PFN of the range to be isolated.
+ * start_pfn/end_pfn must be aligned to pageblock_order.
+ * @migratetype: Migrate type to set in error recovery.
+ * @flags: The following flags are allowed (they can be combined in
+ * a bit mask)
+ * SKIP_HWPOISON - ignore hwpoison pages
+ * REPORT_FAILURE - report details about the failure to
+ * isolate the range
*
* Making page-allocation-type to be MIGRATE_ISOLATE means free pages in
* the range will never be allocated. Any free pages and pages freed in the
- * future will not be allocated again.
- *
- * start_pfn/end_pfn must be aligned to pageblock_order.
- * Return 0 on success and -EBUSY if any part of range cannot be isolated.
+ * future will not be allocated again. If specified range includes migrate types
+ * other than MOVABLE or CMA, this will fail with -EBUSY. For isolating all
+ * pages in the range finally, the caller have to free all pages in the range.
+ * test_page_isolated() can be used for test it.
*
* There is no high level synchronization mechanism that prevents two threads
- * from trying to isolate overlapping ranges. If this happens, one thread
+ * from trying to isolate overlapping ranges. If this happens, one thread
* will notice pageblocks in the overlapping range already set to isolate.
* This happens in set_migratetype_isolate, and set_migratetype_isolate
- * returns an error. We then clean up by restoring the migration type on
- * pageblocks we may have modified and return -EBUSY to caller. This
+ * returns an error. We then clean up by restoring the migration type on
+ * pageblocks we may have modified and return -EBUSY to caller. This
* prevents two threads from simultaneously working on overlapping ranges.
+ *
+ * Return: the number of isolated pageblocks on success and -EBUSY if any part
+ * of range cannot be isolated.
*/
int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
unsigned migratetype, int flags)
@@ -188,6 +197,7 @@ int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
unsigned long pfn;
unsigned long undo_pfn;
struct page *page;
+ int nr_isolate_pageblock = 0;
BUG_ON(!IS_ALIGNED(start_pfn, pageblock_nr_pages));
BUG_ON(!IS_ALIGNED(end_pfn, pageblock_nr_pages));
@@ -196,13 +206,15 @@ int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
pfn < end_pfn;
pfn += pageblock_nr_pages) {
page = __first_valid_page(pfn, pageblock_nr_pages);
- if (page &&
- set_migratetype_isolate(page, migratetype, flags)) {
- undo_pfn = pfn;
- goto undo;
+ if (page) {
+ if (set_migratetype_isolate(page, migratetype, flags)) {
+ undo_pfn = pfn;
+ goto undo;
+ }
+ nr_isolate_pageblock++;
}
}
- return 0;
+ return nr_isolate_pageblock;
undo:
for (pfn = start_pfn;
pfn < undo_pfn;
diff --git a/mm/sparse.c b/mm/sparse.c
index 69904aa6165bf13b89a44d6abf84609fea2076ba..56e057c432f9663439c4cfd38f8cad8f2e6e2c3d 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -567,7 +567,7 @@ void online_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
}
#ifdef CONFIG_MEMORY_HOTREMOVE
-/* Mark all memory sections within the pfn range as online */
+/* Mark all memory sections within the pfn range as offline */
void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn)
{
unsigned long pfn;