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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-03-25 03:53:42 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-03-25 03:53:42 -0300
commit03dd4cb26d967f9588437b0fc9cc0e8353322bb7 (patch)
treefa581f6dc1c0596391690d1f67eceef3af8246dc /mm/swapfile.c
parentd4e493caf788ef44982e131ff9c786546904d934 (diff)
Linux-libre 4.5-gnu
Diffstat (limited to 'mm/swapfile.c')
-rw-r--r--mm/swapfile.c139
1 files changed, 32 insertions, 107 deletions
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 6c67b4265..d2c37365e 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -9,7 +9,6 @@
#include <linux/hugetlb.h>
#include <linux/mman.h>
#include <linux/slab.h>
-#include <linux/export.h>
#include <linux/kernel_stat.h>
#include <linux/swap.h>
#include <linux/vmalloc.h>
@@ -44,6 +43,7 @@
static bool swap_count_continued(struct swap_info_struct *, pgoff_t,
unsigned char);
static void free_swap_count_continuations(struct swap_info_struct *);
+static sector_t map_swap_entry(swp_entry_t, struct block_device**);
DEFINE_SPINLOCK(swap_lock);
static unsigned int nr_swapfiles;
@@ -165,8 +165,6 @@ static void discard_swap_cluster(struct swap_info_struct *si,
int found_extent = 0;
while (nr_pages) {
- struct list_head *lh;
-
if (se->start_page <= start_page &&
start_page < se->start_page + se->nr_pages) {
pgoff_t offset = start_page - se->start_page;
@@ -188,8 +186,7 @@ static void discard_swap_cluster(struct swap_info_struct *si,
break;
}
- lh = se->list.next;
- se = list_entry(lh, struct swap_extent, list);
+ se = list_next_entry(se, list);
}
}
@@ -722,60 +719,6 @@ swp_entry_t get_swap_page_of_type(int type)
return (swp_entry_t) {0};
}
-static unsigned int find_next_to_unuse(struct swap_info_struct *si,
- unsigned int prev, bool frontswap);
-
-void get_swap_range_of_type(int type, swp_entry_t *start, swp_entry_t *end,
- unsigned int limit)
-{
- struct swap_info_struct *si;
- pgoff_t start_at;
- unsigned int i;
-
- *start = swp_entry(0, 0);
- *end = swp_entry(0, 0);
- si = swap_info[type];
- spin_lock(&si->lock);
- if (si && (si->flags & SWP_WRITEOK)) {
- atomic_long_dec(&nr_swap_pages);
- /* This is called for allocating swap entry, not cache */
- start_at = scan_swap_map(si, 1);
- if (start_at) {
- unsigned long stop_at = find_next_to_unuse(si, start_at, 0);
- if (stop_at > start_at)
- stop_at--;
- else
- stop_at = si->max - 1;
- if (stop_at - start_at + 1 > limit)
- stop_at = min_t(unsigned int,
- start_at + limit - 1,
- si->max - 1);
- /* Mark them used */
- for (i = start_at; i <= stop_at; i++)
- si->swap_map[i] = 1;
- /* first page already done above */
- si->inuse_pages += stop_at - start_at;
-
- atomic_long_sub(stop_at - start_at, &nr_swap_pages);
- if (start_at == si->lowest_bit)
- si->lowest_bit = stop_at + 1;
- if (stop_at == si->highest_bit)
- si->highest_bit = start_at - 1;
- if (si->inuse_pages == si->pages) {
- si->lowest_bit = si->max;
- si->highest_bit = 0;
- }
- for (i = start_at + 1; i <= stop_at; i++)
- inc_cluster_info_page(si, si->cluster_info, i);
- si->cluster_next = stop_at + 1;
- *start = swp_entry(type, start_at);
- *end = swp_entry(type, stop_at);
- } else
- atomic_long_inc(&nr_swap_pages);
- }
- spin_unlock(&si->lock);
-}
-
static struct swap_info_struct *swap_info_get(swp_entry_t entry)
{
struct swap_info_struct *p;
@@ -842,14 +785,12 @@ static unsigned char swap_entry_free(struct swap_info_struct *p,
count--;
}
- if (!count)
- mem_cgroup_uncharge_swap(entry);
-
usage = count | has_cache;
p->swap_map[offset] = usage;
/* free if no reference */
if (!usage) {
+ mem_cgroup_uncharge_swap(entry);
dec_cluster_info_page(p, p->cluster_info, offset);
if (offset < p->lowest_bit)
p->lowest_bit = offset;
@@ -957,7 +898,7 @@ int swp_swapcount(swp_entry_t entry)
VM_BUG_ON(page_private(page) != SWP_CONTINUED);
do {
- page = list_entry(page->lru.next, struct page, lru);
+ page = list_next_entry(page, lru);
map = kmap_atomic(page);
tmp_count = map[offset];
kunmap_atomic(map);
@@ -983,6 +924,9 @@ int reuse_swap_page(struct page *page)
VM_BUG_ON_PAGE(!PageLocked(page), page);
if (unlikely(PageKsm(page)))
return 0;
+ /* The page is part of THP and cannot be reused */
+ if (PageTransCompound(page))
+ return 0;
count = page_mapcount(page);
if (count <= 1 && PageSwapCache(page)) {
count += page_swapcount(page);
@@ -1062,7 +1006,7 @@ int free_swap_and_cache(swp_entry_t entry)
* Also recheck PageSwapCache now page is locked (above).
*/
if (PageSwapCache(page) && !PageWriteback(page) &&
- (!page_mapped(page) || vm_swap_full())) {
+ (!page_mapped(page) || mem_cgroup_swap_full(page))) {
delete_from_swap_cache(page);
SetPageDirty(page);
}
@@ -1165,19 +1109,9 @@ unsigned int count_swap_pages(int type, int free)
}
#endif /* CONFIG_HIBERNATION */
-static inline int maybe_same_pte(pte_t pte, pte_t swp_pte)
+static inline int pte_same_as_swp(pte_t pte, pte_t swp_pte)
{
-#ifdef CONFIG_MEM_SOFT_DIRTY
- /*
- * When pte keeps soft dirty bit the pte generated
- * from swap entry does not has it, still it's same
- * pte from logical point of view.
- */
- pte_t swp_pte_dirty = pte_swp_mksoft_dirty(swp_pte);
- return pte_same(pte, swp_pte) || pte_same(pte, swp_pte_dirty);
-#else
- return pte_same(pte, swp_pte);
-#endif
+ return pte_same(pte_swp_clear_soft_dirty(pte), swp_pte);
}
/*
@@ -1199,14 +1133,15 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
if (unlikely(!page))
return -ENOMEM;
- if (mem_cgroup_try_charge(page, vma->vm_mm, GFP_KERNEL, &memcg)) {
+ if (mem_cgroup_try_charge(page, vma->vm_mm, GFP_KERNEL,
+ &memcg, false)) {
ret = -ENOMEM;
goto out_nolock;
}
pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
- if (unlikely(!maybe_same_pte(*pte, swp_entry_to_pte(entry)))) {
- mem_cgroup_cancel_charge(page, memcg);
+ if (unlikely(!pte_same_as_swp(*pte, swp_entry_to_pte(entry)))) {
+ mem_cgroup_cancel_charge(page, memcg, false);
ret = 0;
goto out;
}
@@ -1217,11 +1152,11 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd,
set_pte_at(vma->vm_mm, addr, pte,
pte_mkold(mk_pte(page, vma->vm_page_prot)));
if (page == swapcache) {
- page_add_anon_rmap(page, vma, addr);
- mem_cgroup_commit_charge(page, memcg, true);
+ page_add_anon_rmap(page, vma, addr, false);
+ mem_cgroup_commit_charge(page, memcg, true, false);
} else { /* ksm created a completely new copy */
- page_add_new_anon_rmap(page, vma, addr);
- mem_cgroup_commit_charge(page, memcg, false);
+ page_add_new_anon_rmap(page, vma, addr, false);
+ mem_cgroup_commit_charge(page, memcg, false, false);
lru_cache_add_active_or_unevictable(page, vma);
}
swap_free(entry);
@@ -1263,7 +1198,7 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
* swapoff spends a _lot_ of time in this loop!
* Test inline before going to call unuse_pte.
*/
- if (unlikely(maybe_same_pte(*pte, swp_pte))) {
+ if (unlikely(pte_same_as_swp(*pte, swp_pte))) {
pte_unmap(pte);
ret = unuse_pte(vma, pmd, addr, entry, page);
if (ret)
@@ -1672,7 +1607,7 @@ static void drain_mmlist(void)
* Note that the type of this function is sector_t, but it returns page offset
* into the bdev, not sector offset.
*/
-sector_t map_swap_entry(swp_entry_t entry, struct block_device **bdev)
+static sector_t map_swap_entry(swp_entry_t entry, struct block_device **bdev)
{
struct swap_info_struct *sis;
struct swap_extent *start_se;
@@ -1687,14 +1622,11 @@ sector_t map_swap_entry(swp_entry_t entry, struct block_device **bdev)
se = start_se;
for ( ; ; ) {
- struct list_head *lh;
-
if (se->start_page <= offset &&
offset < (se->start_page + se->nr_pages)) {
return se->start_block + (offset - se->start_page);
}
- lh = se->list.next;
- se = list_entry(lh, struct swap_extent, list);
+ se = list_next_entry(se, list);
sis->curr_swap_extent = se;
BUG_ON(se == start_se); /* It *must* be present */
}
@@ -1718,7 +1650,7 @@ static void destroy_swap_extents(struct swap_info_struct *sis)
while (!list_empty(&sis->first_swap_extent.list)) {
struct swap_extent *se;
- se = list_entry(sis->first_swap_extent.list.next,
+ se = list_first_entry(&sis->first_swap_extent.list,
struct swap_extent, list);
list_del(&se->list);
kfree(se);
@@ -2024,9 +1956,9 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile)
set_blocksize(bdev, old_block_size);
blkdev_put(bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
} else {
- mutex_lock(&inode->i_mutex);
+ inode_lock(inode);
inode->i_flags &= ~S_SWAPFILE;
- mutex_unlock(&inode->i_mutex);
+ inode_unlock(inode);
}
filp_close(swap_file, NULL);
@@ -2251,7 +2183,7 @@ static int claim_swapfile(struct swap_info_struct *p, struct inode *inode)
p->flags |= SWP_BLKDEV;
} else if (S_ISREG(inode->i_mode)) {
p->bdev = inode->i_sb->s_bdev;
- mutex_lock(&inode->i_mutex);
+ inode_lock(inode);
if (IS_SWAPFILE(inode))
return -EBUSY;
} else
@@ -2484,7 +2416,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
mapping = swap_file->f_mapping;
inode = mapping->host;
- /* If S_ISREG(inode->i_mode) will do mutex_lock(&inode->i_mutex); */
+ /* If S_ISREG(inode->i_mode) will do inode_lock(inode); */
error = claim_swapfile(p, inode);
if (unlikely(error))
goto bad_swap;
@@ -2629,7 +2561,7 @@ bad_swap:
vfree(cluster_info);
if (swap_file) {
if (inode && S_ISREG(inode->i_mode)) {
- mutex_unlock(&inode->i_mutex);
+ inode_unlock(inode);
inode = NULL;
}
filp_close(swap_file, NULL);
@@ -2642,7 +2574,7 @@ out:
if (name)
putname(name);
if (inode && S_ISREG(inode->i_mode))
- mutex_unlock(&inode->i_mutex);
+ inode_unlock(inode);
return error;
}
@@ -2806,14 +2738,8 @@ pgoff_t __page_file_index(struct page *page)
VM_BUG_ON_PAGE(!PageSwapCache(page), page);
return swp_offset(swap);
}
-
EXPORT_SYMBOL_GPL(__page_file_index);
-struct swap_info_struct *get_swap_info_struct(unsigned type)
-{
- return swap_info[type];
-}
-
/*
* add_swap_count_continuation - called when a swap count is duplicated
* beyond SWAP_MAP_MAX, it allocates a new page and links that to the entry's
@@ -3019,11 +2945,10 @@ static void free_swap_count_continuations(struct swap_info_struct *si)
struct page *head;
head = vmalloc_to_page(si->swap_map + offset);
if (page_private(head)) {
- struct list_head *this, *next;
- list_for_each_safe(this, next, &head->lru) {
- struct page *page;
- page = list_entry(this, struct page, lru);
- list_del(this);
+ struct page *page, *next;
+
+ list_for_each_entry_safe(page, next, &head->lru, lru) {
+ list_del(&page->lru);
__free_page(page);
}
}