1 files changed, 156 insertions, 41 deletions

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index e2d46adb54b4..65a1b6c69c11 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -14,6 +14,7 @@
 #include <linux/swapops.h>
 #include <linux/mmu_notifier.h>
 #include <linux/page_idle.h>
+#include <linux/shmem_fs.h>
 
 #include <asm/elf.h>
 #include <asm/uaccess.h>
@@ -22,9 +23,13 @@
 
 void task_mem(struct seq_file *m, struct mm_struct *mm)
 {
-	unsigned long data, text, lib, swap, ptes, pmds;
+	unsigned long text, lib, swap, ptes, pmds, anon, file, shmem;
 	unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
 
+	anon = get_mm_counter(mm, MM_ANONPAGES);
+	file = get_mm_counter(mm, MM_FILEPAGES);
+	shmem = get_mm_counter(mm, MM_SHMEMPAGES);
+
 	/*
 	 * Note: to minimize their overhead, mm maintains hiwater_vm and
 	 * hiwater_rss only when about to *lower* total_vm or rss.  Any
@@ -35,11 +40,10 @@ void task_mem(struct seq_file *m, struct mm_struct *mm)
 	hiwater_vm = total_vm = mm->total_vm;
 	if (hiwater_vm < mm->hiwater_vm)
 		hiwater_vm = mm->hiwater_vm;
-	hiwater_rss = total_rss = get_mm_rss(mm);
+	hiwater_rss = total_rss = anon + file + shmem;
 	if (hiwater_rss < mm->hiwater_rss)
 		hiwater_rss = mm->hiwater_rss;
 
-	data = mm->total_vm - mm->shared_vm - mm->stack_vm;
 	text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10;
 	lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text;
 	swap = get_mm_counter(mm, MM_SWAPENTS);
@@ -52,6 +56,9 @@ void task_mem(struct seq_file *m, struct mm_struct *mm)
 		"VmPin:\t%8lu kB\n"
 		"VmHWM:\t%8lu kB\n"
 		"VmRSS:\t%8lu kB\n"
+		"RssAnon:\t%8lu kB\n"
+		"RssFile:\t%8lu kB\n"
+		"RssShmem:\t%8lu kB\n"
 		"VmData:\t%8lu kB\n"
 		"VmStk:\t%8lu kB\n"
 		"VmExe:\t%8lu kB\n"
@@ -65,11 +72,15 @@ void task_mem(struct seq_file *m, struct mm_struct *mm)
 		mm->pinned_vm << (PAGE_SHIFT-10),
 		hiwater_rss << (PAGE_SHIFT-10),
 		total_rss << (PAGE_SHIFT-10),
-		data << (PAGE_SHIFT-10),
+		anon << (PAGE_SHIFT-10),
+		file << (PAGE_SHIFT-10),
+		shmem << (PAGE_SHIFT-10),
+		mm->data_vm << (PAGE_SHIFT-10),
 		mm->stack_vm << (PAGE_SHIFT-10), text, lib,
 		ptes >> 10,
 		pmds >> 10,
 		swap << (PAGE_SHIFT-10));
+	hugetlb_report_usage(m, mm);
 }
 
 unsigned long task_vsize(struct mm_struct *mm)
@@ -81,10 +92,11 @@ unsigned long task_statm(struct mm_struct *mm,
 			 unsigned long *shared, unsigned long *text,
 			 unsigned long *data, unsigned long *resident)
 {
-	*shared = get_mm_counter(mm, MM_FILEPAGES);
+	*shared = get_mm_counter(mm, MM_FILEPAGES) +
+			get_mm_counter(mm, MM_SHMEMPAGES);
 	*text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
 								>> PAGE_SHIFT;
-	*data = mm->total_vm - mm->shared_vm;
+	*data = mm->data_vm + mm->stack_vm;
 	*resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
 	return mm->total_vm;
 }
@@ -446,14 +458,18 @@ struct mem_size_stats {
 	unsigned long anonymous;
 	unsigned long anonymous_thp;
 	unsigned long swap;
+	unsigned long shared_hugetlb;
+	unsigned long private_hugetlb;
 	u64 pss;
 	u64 swap_pss;
+	bool check_shmem_swap;
 };
 
 static void smaps_account(struct mem_size_stats *mss, struct page *page,
-		unsigned long size, bool young, bool dirty)
+		bool compound, bool young, bool dirty)
 {
-	int mapcount;
+	int i, nr = compound ? HPAGE_PMD_NR : 1;
+	unsigned long size = nr * PAGE_SIZE;
 
 	if (PageAnon(page))
 		mss->anonymous += size;
@@ -462,25 +478,52 @@ static void smaps_account(struct mem_size_stats *mss, struct page *page,
 	/* Accumulate the size in pages that have been accessed. */
 	if (young || page_is_young(page) || PageReferenced(page))
 		mss->referenced += size;
-	mapcount = page_mapcount(page);
-	if (mapcount >= 2) {
-		u64 pss_delta;
 
-		if (dirty || PageDirty(page))
-			mss->shared_dirty += size;
-		else
-			mss->shared_clean += size;
-		pss_delta = (u64)size << PSS_SHIFT;
-		do_div(pss_delta, mapcount);
-		mss->pss += pss_delta;
-	} else {
+	/*
+	 * page_count(page) == 1 guarantees the page is mapped exactly once.
+	 * If any subpage of the compound page mapped with PTE it would elevate
+	 * page_count().
+	 */
+	if (page_count(page) == 1) {
 		if (dirty || PageDirty(page))
 			mss->private_dirty += size;
 		else
 			mss->private_clean += size;
 		mss->pss += (u64)size << PSS_SHIFT;
+		return;
 	}
+
+	for (i = 0; i < nr; i++, page++) {
+		int mapcount = page_mapcount(page);
+
+		if (mapcount >= 2) {
+			if (dirty || PageDirty(page))
+				mss->shared_dirty += PAGE_SIZE;
+			else
+				mss->shared_clean += PAGE_SIZE;
+			mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount;
+		} else {
+			if (dirty || PageDirty(page))
+				mss->private_dirty += PAGE_SIZE;
+			else
+				mss->private_clean += PAGE_SIZE;
+			mss->pss += PAGE_SIZE << PSS_SHIFT;
+		}
+	}
+}
+
+#ifdef CONFIG_SHMEM
+static int smaps_pte_hole(unsigned long addr, unsigned long end,
+		struct mm_walk *walk)
+{
+	struct mem_size_stats *mss = walk->private;
+
+	mss->swap += shmem_partial_swap_usage(
+			walk->vma->vm_file->f_mapping, addr, end);
+
+	return 0;
 }
+#endif
 
 static void smaps_pte_entry(pte_t *pte, unsigned long addr,
 		struct mm_walk *walk)
@@ -509,11 +552,25 @@ static void smaps_pte_entry(pte_t *pte, unsigned long addr,
 			}
 		} else if (is_migration_entry(swpent))
 			page = migration_entry_to_page(swpent);
+	} else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap
+							&& pte_none(*pte))) {
+		page = find_get_entry(vma->vm_file->f_mapping,
+						linear_page_index(vma, addr));
+		if (!page)
+			return;
+
+		if (radix_tree_exceptional_entry(page))
+			mss->swap += PAGE_SIZE;
+		else
+			page_cache_release(page);
+
+		return;
 	}
 
 	if (!page)
 		return;
-	smaps_account(mss, page, PAGE_SIZE, pte_young(*pte), pte_dirty(*pte));
+
+	smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte));
 }
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
@@ -529,8 +586,7 @@ static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
 	if (IS_ERR_OR_NULL(page))
 		return;
 	mss->anonymous_thp += HPAGE_PMD_SIZE;
-	smaps_account(mss, page, HPAGE_PMD_SIZE,
-			pmd_young(*pmd), pmd_dirty(*pmd));
+	smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd));
 }
 #else
 static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
@@ -546,7 +602,7 @@ static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 	pte_t *pte;
 	spinlock_t *ptl;
 
-	if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
+	if (pmd_trans_huge_lock(pmd, vma, &ptl)) {
 		smaps_pmd_entry(pmd, addr, walk);
 		spin_unlock(ptl);
 		return 0;
@@ -625,17 +681,74 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
 	seq_putc(m, '\n');
 }
 
+#ifdef CONFIG_HUGETLB_PAGE
+static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
+				 unsigned long addr, unsigned long end,
+				 struct mm_walk *walk)
+{
+	struct mem_size_stats *mss = walk->private;
+	struct vm_area_struct *vma = walk->vma;
+	struct page *page = NULL;
+
+	if (pte_present(*pte)) {
+		page = vm_normal_page(vma, addr, *pte);
+	} else if (is_swap_pte(*pte)) {
+		swp_entry_t swpent = pte_to_swp_entry(*pte);
+
+		if (is_migration_entry(swpent))
+			page = migration_entry_to_page(swpent);
+	}
+	if (page) {
+		int mapcount = page_mapcount(page);
+
+		if (mapcount >= 2)
+			mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
+		else
+			mss->private_hugetlb += huge_page_size(hstate_vma(vma));
+	}
+	return 0;
+}
+#endif /* HUGETLB_PAGE */
+
 static int show_smap(struct seq_file *m, void *v, int is_pid)
 {
 	struct vm_area_struct *vma = v;
 	struct mem_size_stats mss;
 	struct mm_walk smaps_walk = {
 		.pmd_entry = smaps_pte_range,
+#ifdef CONFIG_HUGETLB_PAGE
+		.hugetlb_entry = smaps_hugetlb_range,
+#endif
 		.mm = vma->vm_mm,
 		.private = &mss,
 	};
 
 	memset(&mss, 0, sizeof mss);
+
+#ifdef CONFIG_SHMEM
+	if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) {
+		/*
+		 * For shared or readonly shmem mappings we know that all
+		 * swapped out pages belong to the shmem object, and we can
+		 * obtain the swap value much more efficiently. For private
+		 * writable mappings, we might have COW pages that are
+		 * not affected by the parent swapped out pages of the shmem
+		 * object, so we have to distinguish them during the page walk.
+		 * Unless we know that the shmem object (or the part mapped by
+		 * our VMA) has no swapped out pages at all.
+		 */
+		unsigned long shmem_swapped = shmem_swap_usage(vma);
+
+		if (!shmem_swapped || (vma->vm_flags & VM_SHARED) ||
+					!(vma->vm_flags & VM_WRITE)) {
+			mss.swap = shmem_swapped;
+		} else {
+			mss.check_shmem_swap = true;
+			smaps_walk.pte_hole = smaps_pte_hole;
+		}
+	}
+#endif
+
 	/* mmap_sem is held in m_start */
 	walk_page_vma(vma, &smaps_walk);
 
@@ -652,6 +765,8 @@ static int show_smap(struct seq_file *m, void *v, int is_pid)
 		   "Referenced:     %8lu kB\n"
 		   "Anonymous:      %8lu kB\n"
 		   "AnonHugePages:  %8lu kB\n"
+		   "Shared_Hugetlb: %8lu kB\n"
+		   "Private_Hugetlb: %7lu kB\n"
 		   "Swap:           %8lu kB\n"
 		   "SwapPss:        %8lu kB\n"
 		   "KernelPageSize: %8lu kB\n"
@@ -667,6 +782,8 @@ static int show_smap(struct seq_file *m, void *v, int is_pid)
 		   mss.referenced >> 10,
 		   mss.anonymous >> 10,
 		   mss.anonymous_thp >> 10,
+		   mss.shared_hugetlb >> 10,
+		   mss.private_hugetlb >> 10,
 		   mss.swap >> 10,
 		   (unsigned long)(mss.swap_pss >> (10 + PSS_SHIFT)),
 		   vma_kernel_pagesize(vma) >> 10,
@@ -753,36 +870,34 @@ static inline void clear_soft_dirty(struct vm_area_struct *vma,
 	pte_t ptent = *pte;
 
 	if (pte_present(ptent)) {
+		ptent = ptep_modify_prot_start(vma->vm_mm, addr, pte);
 		ptent = pte_wrprotect(ptent);
-		ptent = pte_clear_flags(ptent, _PAGE_SOFT_DIRTY);
+		ptent = pte_clear_soft_dirty(ptent);
+		ptep_modify_prot_commit(vma->vm_mm, addr, pte, ptent);
 	} else if (is_swap_pte(ptent)) {
 		ptent = pte_swp_clear_soft_dirty(ptent);
+		set_pte_at(vma->vm_mm, addr, pte, ptent);
 	}
-
-	set_pte_at(vma->vm_mm, addr, pte, ptent);
 }
+#else
+static inline void clear_soft_dirty(struct vm_area_struct *vma,
+		unsigned long addr, pte_t *pte)
+{
+}
+#endif
 
+#if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
 		unsigned long addr, pmd_t *pmdp)
 {
-	pmd_t pmd = *pmdp;
+	pmd_t pmd = pmdp_huge_get_and_clear(vma->vm_mm, addr, pmdp);
 
 	pmd = pmd_wrprotect(pmd);
-	pmd = pmd_clear_flags(pmd, _PAGE_SOFT_DIRTY);
-
-	if (vma->vm_flags & VM_SOFTDIRTY)
-		vma->vm_flags &= ~VM_SOFTDIRTY;
+	pmd = pmd_clear_soft_dirty(pmd);
 
 	set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
 }
-
 #else
-
-static inline void clear_soft_dirty(struct vm_area_struct *vma,
-		unsigned long addr, pte_t *pte)
-{
-}
-
 static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
 		unsigned long addr, pmd_t *pmdp)
 {
@@ -798,7 +913,7 @@ static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
 	spinlock_t *ptl;
 	struct page *page;
 
-	if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
+	if (pmd_trans_huge_lock(pmd, vma, &ptl)) {
 		if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
 			clear_soft_dirty_pmd(vma, addr, pmd);
 			goto out;
@@ -1072,7 +1187,7 @@ static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
 	int err = 0;
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
-	if (pmd_trans_huge_lock(pmdp, vma, &ptl) == 1) {
+	if (pmd_trans_huge_lock(pmdp, vma, &ptl)) {
 		u64 flags = 0, frame = 0;
 		pmd_t pmd = *pmdp;
 
@@ -1404,7 +1519,7 @@ static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
 	pte_t *orig_pte;
 	pte_t *pte;
 
-	if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
+	if (pmd_trans_huge_lock(pmd, vma, &ptl)) {
 		pte_t huge_pte = *(pte_t *)pmd;
 		struct page *page;