Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/mm/madvise.c b/mm/madvise.c
index 71d21df..94c343b 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -11,15 +11,18 @@
#include <linux/syscalls.h>
#include <linux/mempolicy.h>
#include <linux/page-isolation.h>
+#include <linux/page_idle.h>
#include <linux/userfaultfd_k.h>
#include <linux/hugetlb.h>
#include <linux/falloc.h>
+#include <linux/fadvise.h>
#include <linux/sched.h>
#include <linux/ksm.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/blkdev.h>
#include <linux/backing-dev.h>
+#include <linux/pagewalk.h>
#include <linux/swap.h>
#include <linux/swapops.h>
#include <linux/shmem_fs.h>
@@ -29,6 +32,11 @@
#include "internal.h"
+struct madvise_walk_private {
+ struct mmu_gather *tlb;
+ bool pageout;
+};
+
/*
* Any behaviour which results in changes to the vma->vm_flags needs to
* take mmap_sem for writing. Others, which simply traverse vmas, need
@@ -40,6 +48,8 @@
case MADV_REMOVE:
case MADV_WILLNEED:
case MADV_DONTNEED:
+ case MADV_COLD:
+ case MADV_PAGEOUT:
case MADV_FREE:
return 0;
default:
@@ -105,28 +115,14 @@
case MADV_MERGEABLE:
case MADV_UNMERGEABLE:
error = ksm_madvise(vma, start, end, behavior, &new_flags);
- if (error) {
- /*
- * madvise() returns EAGAIN if kernel resources, such as
- * slab, are temporarily unavailable.
- */
- if (error == -ENOMEM)
- error = -EAGAIN;
- goto out;
- }
+ if (error)
+ goto out_convert_errno;
break;
case MADV_HUGEPAGE:
case MADV_NOHUGEPAGE:
error = hugepage_madvise(vma, &new_flags, behavior);
- if (error) {
- /*
- * madvise() returns EAGAIN if kernel resources, such as
- * slab, are temporarily unavailable.
- */
- if (error == -ENOMEM)
- error = -EAGAIN;
- goto out;
- }
+ if (error)
+ goto out_convert_errno;
break;
}
@@ -152,15 +148,8 @@
goto out;
}
error = __split_vma(mm, vma, start, 1);
- if (error) {
- /*
- * madvise() returns EAGAIN if kernel resources, such as
- * slab, are temporarily unavailable.
- */
- if (error == -ENOMEM)
- error = -EAGAIN;
- goto out;
- }
+ if (error)
+ goto out_convert_errno;
}
if (end != vma->vm_end) {
@@ -169,15 +158,8 @@
goto out;
}
error = __split_vma(mm, vma, end, 0);
- if (error) {
- /*
- * madvise() returns EAGAIN if kernel resources, such as
- * slab, are temporarily unavailable.
- */
- if (error == -ENOMEM)
- error = -EAGAIN;
- goto out;
- }
+ if (error)
+ goto out_convert_errno;
}
success:
@@ -185,6 +167,14 @@
* vm_flags is protected by the mmap_sem held in write mode.
*/
vma->vm_flags = new_flags;
+
+out_convert_errno:
+ /*
+ * madvise() returns EAGAIN if kernel resources, such as
+ * slab, are temporarily unavailable.
+ */
+ if (error == -ENOMEM)
+ error = -EAGAIN;
out:
return error;
}
@@ -225,19 +215,9 @@
return 0;
}
-static void force_swapin_readahead(struct vm_area_struct *vma,
- unsigned long start, unsigned long end)
-{
- struct mm_walk walk = {
- .mm = vma->vm_mm,
- .pmd_entry = swapin_walk_pmd_entry,
- .private = vma,
- };
-
- walk_page_range(start, end, &walk);
-
- lru_add_drain(); /* Push any new pages onto the LRU now */
-}
+static const struct mm_walk_ops swapin_walk_ops = {
+ .pmd_entry = swapin_walk_pmd_entry,
+};
static void force_shm_swapin_readahead(struct vm_area_struct *vma,
unsigned long start, unsigned long end,
@@ -251,7 +231,7 @@
index = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
page = find_get_entry(mapping, index);
- if (!radix_tree_exceptional_entry(page)) {
+ if (!xa_is_value(page)) {
if (page)
put_page(page);
continue;
@@ -275,11 +255,13 @@
unsigned long start, unsigned long end)
{
struct file *file = vma->vm_file;
+ loff_t offset;
*prev = vma;
#ifdef CONFIG_SWAP
if (!file) {
- force_swapin_readahead(vma, start, end);
+ walk_page_range(vma->vm_mm, start, end, &swapin_walk_ops, vma);
+ lru_add_drain(); /* Push any new pages onto the LRU now */
return 0;
}
@@ -298,12 +280,276 @@
return 0;
}
- start = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
- if (end > vma->vm_end)
- end = vma->vm_end;
- end = ((end - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
+ /*
+ * Filesystem's fadvise may need to take various locks. We need to
+ * explicitly grab a reference because the vma (and hence the
+ * vma's reference to the file) can go away as soon as we drop
+ * mmap_sem.
+ */
+ *prev = NULL; /* tell sys_madvise we drop mmap_sem */
+ get_file(file);
+ up_read(¤t->mm->mmap_sem);
+ offset = (loff_t)(start - vma->vm_start)
+ + ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
+ vfs_fadvise(file, offset, end - start, POSIX_FADV_WILLNEED);
+ fput(file);
+ down_read(¤t->mm->mmap_sem);
+ return 0;
+}
- force_page_cache_readahead(file->f_mapping, file, start, end - start);
+static int madvise_cold_or_pageout_pte_range(pmd_t *pmd,
+ unsigned long addr, unsigned long end,
+ struct mm_walk *walk)
+{
+ struct madvise_walk_private *private = walk->private;
+ struct mmu_gather *tlb = private->tlb;
+ bool pageout = private->pageout;
+ struct mm_struct *mm = tlb->mm;
+ struct vm_area_struct *vma = walk->vma;
+ pte_t *orig_pte, *pte, ptent;
+ spinlock_t *ptl;
+ struct page *page = NULL;
+ LIST_HEAD(page_list);
+
+ if (fatal_signal_pending(current))
+ return -EINTR;
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ if (pmd_trans_huge(*pmd)) {
+ pmd_t orig_pmd;
+ unsigned long next = pmd_addr_end(addr, end);
+
+ tlb_change_page_size(tlb, HPAGE_PMD_SIZE);
+ ptl = pmd_trans_huge_lock(pmd, vma);
+ if (!ptl)
+ return 0;
+
+ orig_pmd = *pmd;
+ if (is_huge_zero_pmd(orig_pmd))
+ goto huge_unlock;
+
+ if (unlikely(!pmd_present(orig_pmd))) {
+ VM_BUG_ON(thp_migration_supported() &&
+ !is_pmd_migration_entry(orig_pmd));
+ goto huge_unlock;
+ }
+
+ page = pmd_page(orig_pmd);
+ if (next - addr != HPAGE_PMD_SIZE) {
+ int err;
+
+ if (page_mapcount(page) != 1)
+ goto huge_unlock;
+
+ get_page(page);
+ spin_unlock(ptl);
+ lock_page(page);
+ err = split_huge_page(page);
+ unlock_page(page);
+ put_page(page);
+ if (!err)
+ goto regular_page;
+ return 0;
+ }
+
+ if (pmd_young(orig_pmd)) {
+ pmdp_invalidate(vma, addr, pmd);
+ orig_pmd = pmd_mkold(orig_pmd);
+
+ set_pmd_at(mm, addr, pmd, orig_pmd);
+ tlb_remove_pmd_tlb_entry(tlb, pmd, addr);
+ }
+
+ ClearPageReferenced(page);
+ test_and_clear_page_young(page);
+ if (pageout) {
+ if (!isolate_lru_page(page)) {
+ if (PageUnevictable(page))
+ putback_lru_page(page);
+ else
+ list_add(&page->lru, &page_list);
+ }
+ } else
+ deactivate_page(page);
+huge_unlock:
+ spin_unlock(ptl);
+ if (pageout)
+ reclaim_pages(&page_list);
+ return 0;
+ }
+
+ if (pmd_trans_unstable(pmd))
+ return 0;
+regular_page:
+#endif
+ tlb_change_page_size(tlb, PAGE_SIZE);
+ orig_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
+ flush_tlb_batched_pending(mm);
+ arch_enter_lazy_mmu_mode();
+ for (; addr < end; pte++, addr += PAGE_SIZE) {
+ ptent = *pte;
+
+ if (pte_none(ptent))
+ continue;
+
+ if (!pte_present(ptent))
+ continue;
+
+ page = vm_normal_page(vma, addr, ptent);
+ if (!page)
+ continue;
+
+ /*
+ * Creating a THP page is expensive so split it only if we
+ * are sure it's worth. Split it if we are only owner.
+ */
+ if (PageTransCompound(page)) {
+ if (page_mapcount(page) != 1)
+ break;
+ get_page(page);
+ if (!trylock_page(page)) {
+ put_page(page);
+ break;
+ }
+ pte_unmap_unlock(orig_pte, ptl);
+ if (split_huge_page(page)) {
+ unlock_page(page);
+ put_page(page);
+ pte_offset_map_lock(mm, pmd, addr, &ptl);
+ break;
+ }
+ unlock_page(page);
+ put_page(page);
+ pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
+ pte--;
+ addr -= PAGE_SIZE;
+ continue;
+ }
+
+ VM_BUG_ON_PAGE(PageTransCompound(page), page);
+
+ if (pte_young(ptent)) {
+ ptent = ptep_get_and_clear_full(mm, addr, pte,
+ tlb->fullmm);
+ ptent = pte_mkold(ptent);
+ set_pte_at(mm, addr, pte, ptent);
+ tlb_remove_tlb_entry(tlb, pte, addr);
+ }
+
+ /*
+ * We are deactivating a page for accelerating reclaiming.
+ * VM couldn't reclaim the page unless we clear PG_young.
+ * As a side effect, it makes confuse idle-page tracking
+ * because they will miss recent referenced history.
+ */
+ ClearPageReferenced(page);
+ test_and_clear_page_young(page);
+ if (pageout) {
+ if (!isolate_lru_page(page)) {
+ if (PageUnevictable(page))
+ putback_lru_page(page);
+ else
+ list_add(&page->lru, &page_list);
+ }
+ } else
+ deactivate_page(page);
+ }
+
+ arch_leave_lazy_mmu_mode();
+ pte_unmap_unlock(orig_pte, ptl);
+ if (pageout)
+ reclaim_pages(&page_list);
+ cond_resched();
+
+ return 0;
+}
+
+static const struct mm_walk_ops cold_walk_ops = {
+ .pmd_entry = madvise_cold_or_pageout_pte_range,
+};
+
+static void madvise_cold_page_range(struct mmu_gather *tlb,
+ struct vm_area_struct *vma,
+ unsigned long addr, unsigned long end)
+{
+ struct madvise_walk_private walk_private = {
+ .pageout = false,
+ .tlb = tlb,
+ };
+
+ tlb_start_vma(tlb, vma);
+ walk_page_range(vma->vm_mm, addr, end, &cold_walk_ops, &walk_private);
+ tlb_end_vma(tlb, vma);
+}
+
+static long madvise_cold(struct vm_area_struct *vma,
+ struct vm_area_struct **prev,
+ unsigned long start_addr, unsigned long end_addr)
+{
+ struct mm_struct *mm = vma->vm_mm;
+ struct mmu_gather tlb;
+
+ *prev = vma;
+ if (!can_madv_lru_vma(vma))
+ return -EINVAL;
+
+ lru_add_drain();
+ tlb_gather_mmu(&tlb, mm, start_addr, end_addr);
+ madvise_cold_page_range(&tlb, vma, start_addr, end_addr);
+ tlb_finish_mmu(&tlb, start_addr, end_addr);
+
+ return 0;
+}
+
+static void madvise_pageout_page_range(struct mmu_gather *tlb,
+ struct vm_area_struct *vma,
+ unsigned long addr, unsigned long end)
+{
+ struct madvise_walk_private walk_private = {
+ .pageout = true,
+ .tlb = tlb,
+ };
+
+ tlb_start_vma(tlb, vma);
+ walk_page_range(vma->vm_mm, addr, end, &cold_walk_ops, &walk_private);
+ tlb_end_vma(tlb, vma);
+}
+
+static inline bool can_do_pageout(struct vm_area_struct *vma)
+{
+ if (vma_is_anonymous(vma))
+ return true;
+ if (!vma->vm_file)
+ return false;
+ /*
+ * paging out pagecache only for non-anonymous mappings that correspond
+ * to the files the calling process could (if tried) open for writing;
+ * otherwise we'd be including shared non-exclusive mappings, which
+ * opens a side channel.
+ */
+ return inode_owner_or_capable(file_inode(vma->vm_file)) ||
+ inode_permission(file_inode(vma->vm_file), MAY_WRITE) == 0;
+}
+
+static long madvise_pageout(struct vm_area_struct *vma,
+ struct vm_area_struct **prev,
+ unsigned long start_addr, unsigned long end_addr)
+{
+ struct mm_struct *mm = vma->vm_mm;
+ struct mmu_gather tlb;
+
+ *prev = vma;
+ if (!can_madv_lru_vma(vma))
+ return -EINVAL;
+
+ if (!can_do_pageout(vma))
+ return 0;
+
+ lru_add_drain();
+ tlb_gather_mmu(&tlb, mm, start_addr, end_addr);
+ madvise_pageout_page_range(&tlb, vma, start_addr, end_addr);
+ tlb_finish_mmu(&tlb, start_addr, end_addr);
+
return 0;
}
@@ -328,7 +574,7 @@
if (pmd_trans_unstable(pmd))
return 0;
- tlb_remove_check_page_size_change(tlb, PAGE_SIZE);
+ tlb_change_page_size(tlb, PAGE_SIZE);
orig_pte = pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
flush_tlb_batched_pending(mm);
arch_enter_lazy_mmu_mode();
@@ -354,7 +600,7 @@
continue;
}
- page = _vm_normal_page(vma, addr, ptent, true);
+ page = vm_normal_page(vma, addr, ptent);
if (!page)
continue;
@@ -440,47 +686,41 @@
return 0;
}
-static void madvise_free_page_range(struct mmu_gather *tlb,
- struct vm_area_struct *vma,
- unsigned long addr, unsigned long end)
-{
- struct mm_walk free_walk = {
- .pmd_entry = madvise_free_pte_range,
- .mm = vma->vm_mm,
- .private = tlb,
- };
-
- tlb_start_vma(tlb, vma);
- walk_page_range(addr, end, &free_walk);
- tlb_end_vma(tlb, vma);
-}
+static const struct mm_walk_ops madvise_free_walk_ops = {
+ .pmd_entry = madvise_free_pte_range,
+};
static int madvise_free_single_vma(struct vm_area_struct *vma,
unsigned long start_addr, unsigned long end_addr)
{
- unsigned long start, end;
struct mm_struct *mm = vma->vm_mm;
+ struct mmu_notifier_range range;
struct mmu_gather tlb;
/* MADV_FREE works for only anon vma at the moment */
if (!vma_is_anonymous(vma))
return -EINVAL;
- start = max(vma->vm_start, start_addr);
- if (start >= vma->vm_end)
+ range.start = max(vma->vm_start, start_addr);
+ if (range.start >= vma->vm_end)
return -EINVAL;
- end = min(vma->vm_end, end_addr);
- if (end <= vma->vm_start)
+ range.end = min(vma->vm_end, end_addr);
+ if (range.end <= vma->vm_start)
return -EINVAL;
+ mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, mm,
+ range.start, range.end);
lru_add_drain();
- tlb_gather_mmu(&tlb, mm, start, end);
+ tlb_gather_mmu(&tlb, mm, range.start, range.end);
update_hiwater_rss(mm);
- mmu_notifier_invalidate_range_start(mm, start, end);
- madvise_free_page_range(&tlb, vma, start, end);
- mmu_notifier_invalidate_range_end(mm, start, end);
- tlb_finish_mmu(&tlb, start, end);
+ mmu_notifier_invalidate_range_start(&range);
+ tlb_start_vma(&tlb, vma);
+ walk_page_range(vma->vm_mm, range.start, range.end,
+ &madvise_free_walk_ops, &tlb);
+ tlb_end_vma(&tlb, vma);
+ mmu_notifier_invalidate_range_end(&range);
+ tlb_finish_mmu(&tlb, range.start, range.end);
return 0;
}
@@ -517,7 +757,7 @@
int behavior)
{
*prev = vma;
- if (!can_madv_dontneed_vma(vma))
+ if (!can_madv_lru_vma(vma))
return -EINVAL;
if (!userfaultfd_remove(vma, start, end)) {
@@ -539,7 +779,7 @@
*/
return -ENOMEM;
}
- if (!can_madv_dontneed_vma(vma))
+ if (!can_madv_lru_vma(vma))
return -EINVAL;
if (end > vma->vm_end) {
/*
@@ -693,6 +933,10 @@
return madvise_remove(vma, prev, start, end);
case MADV_WILLNEED:
return madvise_willneed(vma, prev, start, end);
+ case MADV_COLD:
+ return madvise_cold(vma, prev, start, end);
+ case MADV_PAGEOUT:
+ return madvise_pageout(vma, prev, start, end);
case MADV_FREE:
case MADV_DONTNEED:
return madvise_dontneed_free(vma, prev, start, end, behavior);
@@ -714,6 +958,8 @@
case MADV_WILLNEED:
case MADV_DONTNEED:
case MADV_FREE:
+ case MADV_COLD:
+ case MADV_PAGEOUT:
#ifdef CONFIG_KSM
case MADV_MERGEABLE:
case MADV_UNMERGEABLE:
@@ -808,6 +1054,8 @@
size_t len;
struct blk_plug plug;
+ start = untagged_addr(start);
+
if (!madvise_behavior_valid(behavior))
return error;