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-rw-r--r--include/linux/swap.h7
-rw-r--r--include/linux/swapops.h10
-rw-r--r--mm/memory.c5
-rw-r--r--mm/swapfile.c11
4 files changed, 31 insertions, 2 deletions
diff --git a/include/linux/swap.h b/include/linux/swap.h
index f3ae17b43f20..0c0fed1b348f 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -55,6 +55,10 @@ static inline int current_is_kswapd(void)
* actions on faults.
*/
+#define SWP_SWAPIN_ERROR_NUM 1
+#define SWP_SWAPIN_ERROR (MAX_SWAPFILES + SWP_HWPOISON_NUM + \
+ SWP_MIGRATION_NUM + SWP_DEVICE_NUM + \
+ SWP_PTE_MARKER_NUM)
/*
* PTE markers are used to persist information onto PTEs that are mapped with
* file-backed memories. As its name "PTE" hints, it should only be applied to
@@ -120,7 +124,8 @@ static inline int current_is_kswapd(void)
#define MAX_SWAPFILES \
((1 << MAX_SWAPFILES_SHIFT) - SWP_DEVICE_NUM - \
- SWP_MIGRATION_NUM - SWP_HWPOISON_NUM - SWP_PTE_MARKER_NUM)
+ SWP_MIGRATION_NUM - SWP_HWPOISON_NUM - \
+ SWP_PTE_MARKER_NUM - SWP_SWAPIN_ERROR_NUM)
/*
* Magic header for a swap area. The first part of the union is
diff --git a/include/linux/swapops.h b/include/linux/swapops.h
index fe220df499f1..f24775b41880 100644
--- a/include/linux/swapops.h
+++ b/include/linux/swapops.h
@@ -108,6 +108,16 @@ static inline void *swp_to_radix_entry(swp_entry_t entry)
return xa_mk_value(entry.val);
}
+static inline swp_entry_t make_swapin_error_entry(struct page *page)
+{
+ return swp_entry(SWP_SWAPIN_ERROR, page_to_pfn(page));
+}
+
+static inline int is_swapin_error_entry(swp_entry_t entry)
+{
+ return swp_type(entry) == SWP_SWAPIN_ERROR;
+}
+
#if IS_ENABLED(CONFIG_DEVICE_PRIVATE)
static inline swp_entry_t make_readable_device_private_entry(pgoff_t offset)
{
diff --git a/mm/memory.c b/mm/memory.c
index 2bf5bca39567..54d106e0c999 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1487,7 +1487,8 @@ again:
/* Only drop the uffd-wp marker if explicitly requested */
if (!zap_drop_file_uffd_wp(details))
continue;
- } else if (is_hwpoison_entry(entry)) {
+ } else if (is_hwpoison_entry(entry) ||
+ is_swapin_error_entry(entry)) {
if (!should_zap_cows(details))
continue;
} else {
@@ -3727,6 +3728,8 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
ret = vmf->page->pgmap->ops->migrate_to_ram(vmf);
} else if (is_hwpoison_entry(entry)) {
ret = VM_FAULT_HWPOISON;
+ } else if (is_swapin_error_entry(entry)) {
+ ret = VM_FAULT_SIGBUS;
} else if (is_pte_marker_entry(entry)) {
ret = handle_pte_marker(vmf);
} else {
diff --git a/mm/swapfile.c b/mm/swapfile.c
index a0eb690d9926..b86d1cc8d00b 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1788,6 +1788,17 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
goto out;
}
+ if (unlikely(!PageUptodate(page))) {
+ pte_t pteval;
+
+ dec_mm_counter(vma->vm_mm, MM_SWAPENTS);
+ pteval = swp_entry_to_pte(make_swapin_error_entry(page));
+ set_pte_at(vma->vm_mm, addr, pte, pteval);
+ swap_free(entry);
+ ret = 0;
+ goto out;
+ }
+
/* See do_swap_page() */
BUG_ON(!PageAnon(page) && PageMappedToDisk(page));
BUG_ON(PageAnon(page) && PageAnonExclusive(page));