aboutsummaryrefslogtreecommitdiff
path: root/fs/proc/page.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/proc/page.c')
-rw-r--r--fs/proc/page.c42
1 files changed, 19 insertions, 23 deletions
diff --git a/fs/proc/page.c b/fs/proc/page.c
index 2fb64bdb64eb..b7a5c84b5819 100644
--- a/fs/proc/page.c
+++ b/fs/proc/page.c
@@ -37,21 +37,19 @@ static inline unsigned long get_max_dump_pfn(void)
#endif
}
-/* /proc/kpagecount - an array exposing page counts
+/* /proc/kpagecount - an array exposing page mapcounts
*
* Each entry is a u64 representing the corresponding
- * physical page count.
+ * physical page mapcount.
*/
static ssize_t kpagecount_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
const unsigned long max_dump_pfn = get_max_dump_pfn();
u64 __user *out = (u64 __user *)buf;
- struct page *ppage;
unsigned long src = *ppos;
unsigned long pfn;
ssize_t ret = 0;
- u64 pcount;
pfn = src / KPMSIZE;
if (src & KPMMASK || count & KPMMASK)
@@ -61,18 +59,19 @@ static ssize_t kpagecount_read(struct file *file, char __user *buf,
count = min_t(unsigned long, count, (max_dump_pfn * KPMSIZE) - src);
while (count > 0) {
+ struct page *page;
+ u64 mapcount = 0;
+
/*
* TODO: ZONE_DEVICE support requires to identify
* memmaps that were actually initialized.
*/
- ppage = pfn_to_online_page(pfn);
-
- if (!ppage)
- pcount = 0;
- else
- pcount = page_mapcount(ppage);
+ page = pfn_to_online_page(pfn);
+ if (page)
+ mapcount = folio_precise_page_mapcount(page_folio(page),
+ page);
- if (put_user(pcount, out)) {
+ if (put_user(mapcount, out)) {
ret = -EFAULT;
break;
}
@@ -148,19 +147,16 @@ u64 stable_page_flags(const struct page *page)
u |= 1 << KPF_COMPOUND_TAIL;
if (folio_test_hugetlb(folio))
u |= 1 << KPF_HUGE;
- /*
- * We need to check PageLRU/PageAnon
- * to make sure a given page is a thp, not a non-huge compound page.
- */
- else if (folio_test_large(folio)) {
- if ((k & (1 << PG_lru)) || is_anon)
- u |= 1 << KPF_THP;
- else if (is_huge_zero_folio(folio)) {
- u |= 1 << KPF_ZERO_PAGE;
- u |= 1 << KPF_THP;
- }
- } else if (is_zero_pfn(page_to_pfn(page)))
+ else if (folio_test_large(folio) &&
+ folio_test_large_rmappable(folio)) {
+ /* Note: we indicate any THPs here, not just PMD-sized ones */
+ u |= 1 << KPF_THP;
+ } else if (is_huge_zero_folio(folio)) {
u |= 1 << KPF_ZERO_PAGE;
+ u |= 1 << KPF_THP;
+ } else if (is_zero_folio(folio)) {
+ u |= 1 << KPF_ZERO_PAGE;
+ }
/*
* Caveats on high order pages: PG_buddy and PG_slab will only be set