#include <linux/huge_mm.h>
#include <linux/shmem_fs.h>
#include "internal.h"
+#include "swap.h"
/*
* swapper_space is a fiction, retained to simplify the path through
*/
static const struct address_space_operations swap_aops = {
.writepage = swap_writepage,
- .dirty_folio = swap_dirty_folio,
+ .dirty_folio = noop_dirty_folio,
#ifdef CONFIG_MIGRATION
- .migratepage = migrate_page,
+ .migrate_folio = migrate_folio,
#endif
};
}
/*
- * add_to_swap_cache resembles add_to_page_cache_locked on swapper_space,
+ * add_to_swap_cache resembles filemap_add_folio on swapper_space,
* but sets SwapCache flag and private instead of mapping and index.
*/
int add_to_swap_cache(struct page *page, swp_entry_t entry,
}
/**
- * add_to_swap - allocate swap space for a page
- * @page: page we want to move to swap
+ * add_to_swap - allocate swap space for a folio
+ * @folio: folio we want to move to swap
*
- * Allocate swap space for the page and add the page to the
- * swap cache. Caller needs to hold the page lock.
+ * Allocate swap space for the folio and add the folio to the
+ * swap cache.
+ *
+ * Context: Caller needs to hold the folio lock.
+ * Return: Whether the folio was added to the swap cache.
*/
-int add_to_swap(struct page *page)
+bool add_to_swap(struct folio *folio)
{
swp_entry_t entry;
int err;
- VM_BUG_ON_PAGE(!PageLocked(page), page);
- VM_BUG_ON_PAGE(!PageUptodate(page), page);
+ VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
+ VM_BUG_ON_FOLIO(!folio_test_uptodate(folio), folio);
- entry = get_swap_page(page);
+ entry = folio_alloc_swap(folio);
if (!entry.val)
- return 0;
+ return false;
/*
* XArray node allocations from PF_MEMALLOC contexts could
/*
* Add it to the swap cache.
*/
- err = add_to_swap_cache(page, entry,
+ err = add_to_swap_cache(&folio->page, entry,
__GFP_HIGH|__GFP_NOMEMALLOC|__GFP_NOWARN, NULL);
if (err)
/*
*/
goto fail;
/*
- * Normally the page will be dirtied in unmap because its pte should be
- * dirty. A special case is MADV_FREE page. The page's pte could have
- * dirty bit cleared but the page's SwapBacked bit is still set because
- * clearing the dirty bit and SwapBacked bit has no lock protected. For
- * such page, unmap will not set dirty bit for it, so page reclaim will
- * not write the page out. This can cause data corruption when the page
- * is swap in later. Always setting the dirty bit for the page solves
- * the problem.
+ * Normally the folio will be dirtied in unmap because its
+ * pte should be dirty. A special case is MADV_FREE page. The
+ * page's pte could have dirty bit cleared but the folio's
+ * SwapBacked flag is still set because clearing the dirty bit
+ * and SwapBacked flag has no lock protected. For such folio,
+ * unmap will not set dirty bit for it, so folio reclaim will
+ * not write the folio out. This can cause data corruption when
+ * the folio is swapped in later. Always setting the dirty flag
+ * for the folio solves the problem.
*/
- set_page_dirty(page);
+ folio_mark_dirty(folio);
- return 1;
+ return true;
fail:
- put_swap_page(page, entry);
- return 0;
+ put_swap_page(&folio->page, entry);
+ return false;
}
/*
return NULL;
swp = radix_to_swp_entry(page);
+ /* There might be swapin error entries in shmem mapping. */
+ if (non_swap_entry(swp))
+ return NULL;
/* Prevent swapoff from happening to us */
si = get_swap_device(swp);
if (!si)
* the swap entry is no longer in use.
*/
struct page *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
- struct vm_area_struct *vma, unsigned long addr, bool do_poll)
+ struct vm_area_struct *vma,
+ unsigned long addr, bool do_poll,
+ struct swap_iocb **plug)
{
bool page_was_allocated;
struct page *retpage = __read_swap_cache_async(entry, gfp_mask,
vma, addr, &page_was_allocated);
if (page_was_allocated)
- swap_readpage(retpage, do_poll);
+ swap_readpage(retpage, do_poll, plug);
return retpage;
}
unsigned long mask;
struct swap_info_struct *si = swp_swap_info(entry);
struct blk_plug plug;
+ struct swap_iocb *splug = NULL;
bool do_poll = true, page_allocated;
struct vm_area_struct *vma = vmf->vma;
unsigned long addr = vmf->address;
if (!page)
continue;
if (page_allocated) {
- swap_readpage(page, false);
+ swap_readpage(page, false, &splug);
if (offset != entry_offset) {
SetPageReadahead(page);
count_vm_event(SWAP_RA);
put_page(page);
}
blk_finish_plug(&plug);
+ swap_read_unplug(splug);
lru_add_drain(); /* Push any new pages onto the LRU now */
skip:
- return read_swap_cache_async(entry, gfp_mask, vma, addr, do_poll);
+ /* The page was likely read above, so no need for plugging here */
+ return read_swap_cache_async(entry, gfp_mask, vma, addr, do_poll, NULL);
}
int init_swap_address_space(unsigned int type, unsigned long nr_pages)
struct vm_fault *vmf)
{
struct blk_plug plug;
+ struct swap_iocb *splug = NULL;
struct vm_area_struct *vma = vmf->vma;
struct page *page;
pte_t *pte, pentry;
for (i = 0, pte = ra_info.ptes; i < ra_info.nr_pte;
i++, pte++) {
pentry = *pte;
- if (pte_none(pentry))
- continue;
- if (pte_present(pentry))
+ if (!is_swap_pte(pentry))
continue;
entry = pte_to_swp_entry(pentry);
if (unlikely(non_swap_entry(entry)))
if (!page)
continue;
if (page_allocated) {
- swap_readpage(page, false);
+ swap_readpage(page, false, &splug);
if (i != ra_info.offset) {
SetPageReadahead(page);
count_vm_event(SWAP_RA);
put_page(page);
}
blk_finish_plug(&plug);
+ swap_read_unplug(splug);
lru_add_drain();
skip:
+ /* The page was likely read above, so no need for plugging here */
return read_swap_cache_async(fentry, gfp_mask, vma, vmf->address,
- ra_info.win == 1);
+ ra_info.win == 1, NULL);
}
/**
struct kobj_attribute *attr,
const char *buf, size_t count)
{
- if (!strncmp(buf, "true", 4) || !strncmp(buf, "1", 1))
- enable_vma_readahead = true;
- else if (!strncmp(buf, "false", 5) || !strncmp(buf, "0", 1))
- enable_vma_readahead = false;
- else
- return -EINVAL;
+ ssize_t ret;
+
+ ret = kstrtobool(buf, &enable_vma_readahead);
+ if (ret)
+ return ret;
return count;
}
-static struct kobj_attribute vma_ra_enabled_attr =
- __ATTR(vma_ra_enabled, 0644, vma_ra_enabled_show,
- vma_ra_enabled_store);
+static struct kobj_attribute vma_ra_enabled_attr = __ATTR_RW(vma_ra_enabled);
static struct attribute *swap_attrs[] = {
&vma_ra_enabled_attr.attr,
projects / linux-2.6-microblaze.git / blobdiff