summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2024-07-10 14:59:41 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2024-07-10 14:59:41 -0700
commit9d9a2f29aefdadc86e450308ff056017a209c755 (patch)
treedd6d605bc70d9b55e6aff414839cdb81c9b71131
parentef2b7eb55e10294f4f384f21506ef20a6184128c (diff)
parentf708f6970cc9d6bac71da45c129482092e710537 (diff)
Merge tag 'mm-hotfixes-stable-2024-07-10-13-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton: "21 hotfixes, 15 of which are cc:stable. No identifiable theme here - all are singleton patches, 19 are for MM" * tag 'mm-hotfixes-stable-2024-07-10-13-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (21 commits) mm/hugetlb: fix kernel NULL pointer dereference when migrating hugetlb folio mm/hugetlb: fix potential race in __update_and_free_hugetlb_folio() filemap: replace pte_offset_map() with pte_offset_map_nolock() arch/xtensa: always_inline get_current() and current_thread_info() sched.h: always_inline alloc_tag_{save|restore} to fix modpost warnings MAINTAINERS: mailmap: update Lorenzo Stoakes's email address mm: fix crashes from deferred split racing folio migration lib/build_OID_registry: avoid non-destructive substitution for Perl < 5.13.2 compat mm: gup: stop abusing try_grab_folio nilfs2: fix kernel bug on rename operation of broken directory mm/hugetlb_vmemmap: fix race with speculative PFN walkers cachestat: do not flush stats in recency check mm/shmem: disable PMD-sized page cache if needed mm/filemap: skip to create PMD-sized page cache if needed mm/readahead: limit page cache size in page_cache_ra_order() mm/filemap: make MAX_PAGECACHE_ORDER acceptable to xarray mm/damon/core: merge regions aggressively when max_nr_regions is unmet Fix userfaultfd_api to return EINVAL as expected mm: vmalloc: check if a hash-index is in cpu_possible_mask mm: prevent derefencing NULL ptr in pfn_section_valid() ...
-rw-r--r--.mailmap1
-rw-r--r--MAINTAINERS2
-rw-r--r--arch/xtensa/include/asm/current.h2
-rw-r--r--arch/xtensa/include/asm/thread_info.h2
-rw-r--r--fs/nilfs2/dir.c32
-rw-r--r--fs/userfaultfd.c7
-rw-r--r--include/linux/mmzone.h3
-rw-r--r--include/linux/page_ref.h57
-rw-r--r--include/linux/pagemap.h11
-rw-r--r--include/linux/sched.h4
-rw-r--r--include/linux/swap.h3
-rwxr-xr-xlib/build_OID_registry4
-rw-r--r--mm/damon/core.c23
-rw-r--r--mm/filemap.c20
-rw-r--r--mm/gup.c291
-rw-r--r--mm/huge_memory.c2
-rw-r--r--mm/hugetlb.c70
-rw-r--r--mm/hugetlb_vmemmap.c16
-rw-r--r--mm/internal.h4
-rw-r--r--mm/memcontrol.c11
-rw-r--r--mm/migrate.c13
-rw-r--r--mm/readahead.c8
-rw-r--r--mm/shmem.c15
-rw-r--r--mm/vmalloc.c10
-rw-r--r--mm/workingset.c14
25 files changed, 339 insertions, 286 deletions
diff --git a/.mailmap b/.mailmap
index a6c619e22efc..81ac1e17ac3c 100644
--- a/.mailmap
+++ b/.mailmap
@@ -384,6 +384,7 @@ Li Yang <leoyang.li@nxp.com> <leoli@freescale.com>
Li Yang <leoyang.li@nxp.com> <leo@zh-kernel.org>
Lior David <quic_liord@quicinc.com> <liord@codeaurora.org>
Lorenzo Pieralisi <lpieralisi@kernel.org> <lorenzo.pieralisi@arm.com>
+Lorenzo Stoakes <lorenzo.stoakes@oracle.com> <lstoakes@gmail.com>
Luca Ceresoli <luca.ceresoli@bootlin.com> <luca@lucaceresoli.net>
Lukasz Luba <lukasz.luba@arm.com> <l.luba@partner.samsung.com>
Luo Jie <quic_luoj@quicinc.com> <luoj@codeaurora.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index da5352dbd4f3..2a4d4b3a9b40 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14472,7 +14472,7 @@ MEMORY MAPPING
M: Andrew Morton <akpm@linux-foundation.org>
R: Liam R. Howlett <Liam.Howlett@oracle.com>
R: Vlastimil Babka <vbabka@suse.cz>
-R: Lorenzo Stoakes <lstoakes@gmail.com>
+R: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
L: linux-mm@kvack.org
S: Maintained
W: http://www.linux-mm.org
diff --git a/arch/xtensa/include/asm/current.h b/arch/xtensa/include/asm/current.h
index 08010dbf5e09..df275d554788 100644
--- a/arch/xtensa/include/asm/current.h
+++ b/arch/xtensa/include/asm/current.h
@@ -19,7 +19,7 @@
struct task_struct;
-static inline struct task_struct *get_current(void)
+static __always_inline struct task_struct *get_current(void)
{
return current_thread_info()->task;
}
diff --git a/arch/xtensa/include/asm/thread_info.h b/arch/xtensa/include/asm/thread_info.h
index 326db1c1d5d8..e0dffcc43b9e 100644
--- a/arch/xtensa/include/asm/thread_info.h
+++ b/arch/xtensa/include/asm/thread_info.h
@@ -91,7 +91,7 @@ struct thread_info {
}
/* how to get the thread information struct from C */
-static inline struct thread_info *current_thread_info(void)
+static __always_inline struct thread_info *current_thread_info(void)
{
struct thread_info *ti;
__asm__("extui %0, a1, 0, "__stringify(CURRENT_SHIFT)"\n\t"
diff --git a/fs/nilfs2/dir.c b/fs/nilfs2/dir.c
index dddfa604491a..4a29b0138d75 100644
--- a/fs/nilfs2/dir.c
+++ b/fs/nilfs2/dir.c
@@ -383,11 +383,39 @@ found:
struct nilfs_dir_entry *nilfs_dotdot(struct inode *dir, struct folio **foliop)
{
- struct nilfs_dir_entry *de = nilfs_get_folio(dir, 0, foliop);
+ struct folio *folio;
+ struct nilfs_dir_entry *de, *next_de;
+ size_t limit;
+ char *msg;
+ de = nilfs_get_folio(dir, 0, &folio);
if (IS_ERR(de))
return NULL;
- return nilfs_next_entry(de);
+
+ limit = nilfs_last_byte(dir, 0); /* is a multiple of chunk size */
+ if (unlikely(!limit || le64_to_cpu(de->inode) != dir->i_ino ||
+ !nilfs_match(1, ".", de))) {
+ msg = "missing '.'";
+ goto fail;
+ }
+
+ next_de = nilfs_next_entry(de);
+ /*
+ * If "next_de" has not reached the end of the chunk, there is
+ * at least one more record. Check whether it matches "..".
+ */
+ if (unlikely((char *)next_de == (char *)de + nilfs_chunk_size(dir) ||
+ !nilfs_match(2, "..", next_de))) {
+ msg = "missing '..'";
+ goto fail;
+ }
+ *foliop = folio;
+ return next_de;
+
+fail:
+ nilfs_error(dir->i_sb, "directory #%lu %s", dir->i_ino, msg);
+ folio_release_kmap(folio, de);
+ return NULL;
}
ino_t nilfs_inode_by_name(struct inode *dir, const struct qstr *qstr)
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index eee7320ab0b0..17e409ceaa33 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -2057,7 +2057,7 @@ static int userfaultfd_api(struct userfaultfd_ctx *ctx,
goto out;
features = uffdio_api.features;
ret = -EINVAL;
- if (uffdio_api.api != UFFD_API || (features & ~UFFD_API_FEATURES))
+ if (uffdio_api.api != UFFD_API)
goto err_out;
ret = -EPERM;
if ((features & UFFD_FEATURE_EVENT_FORK) && !capable(CAP_SYS_PTRACE))
@@ -2081,6 +2081,11 @@ static int userfaultfd_api(struct userfaultfd_ctx *ctx,
uffdio_api.features &= ~UFFD_FEATURE_WP_UNPOPULATED;
uffdio_api.features &= ~UFFD_FEATURE_WP_ASYNC;
#endif
+
+ ret = -EINVAL;
+ if (features & ~uffdio_api.features)
+ goto err_out;
+
uffdio_api.ioctls = UFFD_API_IOCTLS;
ret = -EFAULT;
if (copy_to_user(buf, &uffdio_api, sizeof(uffdio_api)))
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 586a8f0104d7..1dc6248feb83 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -1979,8 +1979,9 @@ static inline int subsection_map_index(unsigned long pfn)
static inline int pfn_section_valid(struct mem_section *ms, unsigned long pfn)
{
int idx = subsection_map_index(pfn);
+ struct mem_section_usage *usage = READ_ONCE(ms->usage);
- return test_bit(idx, READ_ONCE(ms->usage)->subsection_map);
+ return usage ? test_bit(idx, usage->subsection_map) : 0;
}
#else
static inline int pfn_section_valid(struct mem_section *ms, unsigned long pfn)
diff --git a/include/linux/page_ref.h b/include/linux/page_ref.h
index 1acf5bac7f50..8c236c651d1d 100644
--- a/include/linux/page_ref.h
+++ b/include/linux/page_ref.h
@@ -230,7 +230,13 @@ static inline int folio_ref_dec_return(struct folio *folio)
static inline bool page_ref_add_unless(struct page *page, int nr, int u)
{
- bool ret = atomic_add_unless(&page->_refcount, nr, u);
+ bool ret = false;
+
+ rcu_read_lock();
+ /* avoid writing to the vmemmap area being remapped */
+ if (!page_is_fake_head(page) && page_ref_count(page) != u)
+ ret = atomic_add_unless(&page->_refcount, nr, u);
+ rcu_read_unlock();
if (page_ref_tracepoint_active(page_ref_mod_unless))
__page_ref_mod_unless(page, nr, ret);
@@ -258,54 +264,9 @@ static inline bool folio_try_get(struct folio *folio)
return folio_ref_add_unless(folio, 1, 0);
}
-static inline bool folio_ref_try_add_rcu(struct folio *folio, int count)
-{
-#ifdef CONFIG_TINY_RCU
- /*
- * The caller guarantees the folio will not be freed from interrupt
- * context, so (on !SMP) we only need preemption to be disabled
- * and TINY_RCU does that for us.
- */
-# ifdef CONFIG_PREEMPT_COUNT
- VM_BUG_ON(!in_atomic() && !irqs_disabled());
-# endif
- VM_BUG_ON_FOLIO(folio_ref_count(folio) == 0, folio);
- folio_ref_add(folio, count);
-#else
- if (unlikely(!folio_ref_add_unless(folio, count, 0))) {
- /* Either the folio has been freed, or will be freed. */
- return false;
- }
-#endif
- return true;
-}
-
-/**
- * folio_try_get_rcu - Attempt to increase the refcount on a folio.
- * @folio: The folio.
- *
- * This is a version of folio_try_get() optimised for non-SMP kernels.
- * If you are still holding the rcu_read_lock() after looking up the
- * page and know that the page cannot have its refcount decreased to
- * zero in interrupt context, you can use this instead of folio_try_get().
- *
- * Example users include get_user_pages_fast() (as pages are not unmapped
- * from interrupt context) and the page cache lookups (as pages are not
- * truncated from interrupt context). We also know that pages are not
- * frozen in interrupt context for the purposes of splitting or migration.
- *
- * You can also use this function if you're holding a lock that prevents
- * pages being frozen & removed; eg the i_pages lock for the page cache
- * or the mmap_lock or page table lock for page tables. In this case,
- * it will always succeed, and you could have used a plain folio_get(),
- * but it's sometimes more convenient to have a common function called
- * from both locked and RCU-protected contexts.
- *
- * Return: True if the reference count was successfully incremented.
- */
-static inline bool folio_try_get_rcu(struct folio *folio)
+static inline bool folio_ref_try_add(struct folio *folio, int count)
{
- return folio_ref_try_add_rcu(folio, 1);
+ return folio_ref_add_unless(folio, count, 0);
}
static inline int page_ref_freeze(struct page *page, int count)
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 59f1df0cde5a..a0a026d2d244 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -354,11 +354,18 @@ static inline void mapping_set_gfp_mask(struct address_space *m, gfp_t mask)
* a good order (that's 1MB if you're using 4kB pages)
*/
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-#define MAX_PAGECACHE_ORDER HPAGE_PMD_ORDER
+#define PREFERRED_MAX_PAGECACHE_ORDER HPAGE_PMD_ORDER
#else
-#define MAX_PAGECACHE_ORDER 8
+#define PREFERRED_MAX_PAGECACHE_ORDER 8
#endif
+/*
+ * xas_split_alloc() does not support arbitrary orders. This implies no
+ * 512MB THP on ARM64 with 64KB base page size.
+ */
+#define MAX_XAS_ORDER (XA_CHUNK_SHIFT * 2 - 1)
+#define MAX_PAGECACHE_ORDER min(MAX_XAS_ORDER, PREFERRED_MAX_PAGECACHE_ORDER)
+
/**
* mapping_set_large_folios() - Indicate the file supports large folios.
* @mapping: The file.
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 61591ac6eab6..a5f4b48fca18 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -2192,13 +2192,13 @@ static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); }
extern void sched_set_stop_task(int cpu, struct task_struct *stop);
#ifdef CONFIG_MEM_ALLOC_PROFILING
-static inline struct alloc_tag *alloc_tag_save(struct alloc_tag *tag)
+static __always_inline struct alloc_tag *alloc_tag_save(struct alloc_tag *tag)
{
swap(current->alloc_tag, tag);
return tag;
}
-static inline void alloc_tag_restore(struct alloc_tag *tag, struct alloc_tag *old)
+static __always_inline void alloc_tag_restore(struct alloc_tag *tag, struct alloc_tag *old)
{
#ifdef CONFIG_MEM_ALLOC_PROFILING_DEBUG
WARN(current->alloc_tag != tag, "current->alloc_tag was changed:\n");
diff --git a/include/linux/swap.h b/include/linux/swap.h
index bd450023b9a4..e685e93ba354 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -354,7 +354,8 @@ static inline swp_entry_t page_swap_entry(struct page *page)
}
/* linux/mm/workingset.c */
-bool workingset_test_recent(void *shadow, bool file, bool *workingset);
+bool workingset_test_recent(void *shadow, bool file, bool *workingset,
+ bool flush);
void workingset_age_nonresident(struct lruvec *lruvec, unsigned long nr_pages);
void *workingset_eviction(struct folio *folio, struct mem_cgroup *target_memcg);
void workingset_refault(struct folio *folio, void *shadow);
diff --git a/lib/build_OID_registry b/lib/build_OID_registry
index 56d8bafeb848..8267e8d71338 100755
--- a/lib/build_OID_registry
+++ b/lib/build_OID_registry
@@ -38,7 +38,9 @@ close IN_FILE || die;
#
open C_FILE, ">$ARGV[1]" or die;
print C_FILE "/*\n";
-print C_FILE " * Automatically generated by ", $0 =~ s#^\Q$abs_srctree/\E##r, ". Do not edit\n";
+my $scriptname = $0;
+$scriptname =~ s#^\Q$abs_srctree/\E##;
+print C_FILE " * Automatically generated by ", $scriptname, ". Do not edit\n";
print C_FILE " */\n";
#
diff --git a/mm/damon/core.c b/mm/damon/core.c
index 6392f1cc97a3..e66823d6b10b 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -1358,14 +1358,31 @@ static void damon_merge_regions_of(struct damon_target *t, unsigned int thres,
* access frequencies are similar. This is for minimizing the monitoring
* overhead under the dynamically changeable access pattern. If a merge was
* unnecessarily made, later 'kdamond_split_regions()' will revert it.
+ *
+ * The total number of regions could be higher than the user-defined limit,
+ * max_nr_regions for some cases. For example, the user can update
+ * max_nr_regions to a number that lower than the current number of regions
+ * while DAMON is running. For such a case, repeat merging until the limit is
+ * met while increasing @threshold up to possible maximum level.
*/
static void kdamond_merge_regions(struct damon_ctx *c, unsigned int threshold,
unsigned long sz_limit)
{
struct damon_target *t;
-
- damon_for_each_target(t, c)
- damon_merge_regions_of(t, threshold, sz_limit);
+ unsigned int nr_regions;
+ unsigned int max_thres;
+
+ max_thres = c->attrs.aggr_interval /
+ (c->attrs.sample_interval ? c->attrs.sample_interval : 1);
+ do {
+ nr_regions = 0;
+ damon_for_each_target(t, c) {
+ damon_merge_regions_of(t, threshold, sz_limit);
+ nr_regions += damon_nr_regions(t);
+ }
+ threshold = max(1, threshold * 2);
+ } while (nr_regions > c->attrs.max_nr_regions &&
+ threshold / 2 < max_thres);
}
/*
diff --git a/mm/filemap.c b/mm/filemap.c
index 876cc64aadd7..657bcd887fdb 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1847,7 +1847,7 @@ repeat:
if (!folio || xa_is_value(folio))
goto out;
- if (!folio_try_get_rcu(folio))
+ if (!folio_try_get(folio))
goto repeat;
if (unlikely(folio != xas_reload(&xas))) {
@@ -2001,7 +2001,7 @@ retry:
if (!folio || xa_is_value(folio))
return folio;
- if (!folio_try_get_rcu(folio))
+ if (!folio_try_get(folio))
goto reset;
if (unlikely(folio != xas_reload(xas))) {
@@ -2181,7 +2181,7 @@ unsigned filemap_get_folios_contig(struct address_space *mapping,
if (xa_is_value(folio))
goto update_start;
- if (!folio_try_get_rcu(folio))
+ if (!folio_try_get(folio))
goto retry;
if (unlikely(folio != xas_reload(&xas)))
@@ -2313,7 +2313,7 @@ static void filemap_get_read_batch(struct address_space *mapping,
break;
if (xa_is_sibling(folio))
break;
- if (!folio_try_get_rcu(folio))
+ if (!folio_try_get(folio))
goto retry;
if (unlikely(folio != xas_reload(&xas)))
@@ -3124,7 +3124,7 @@ static struct file *do_sync_mmap_readahead(struct vm_fault *vmf)
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
/* Use the readahead code, even if readahead is disabled */
- if (vm_flags & VM_HUGEPAGE) {
+ if ((vm_flags & VM_HUGEPAGE) && HPAGE_PMD_ORDER <= MAX_PAGECACHE_ORDER) {
fpin = maybe_unlock_mmap_for_io(vmf, fpin);
ractl._index &= ~((unsigned long)HPAGE_PMD_NR - 1);
ra->size = HPAGE_PMD_NR;
@@ -3231,7 +3231,8 @@ static vm_fault_t filemap_fault_recheck_pte_none(struct vm_fault *vmf)
if (!(vmf->flags & FAULT_FLAG_ORIG_PTE_VALID))
return 0;
- ptep = pte_offset_map(vmf->pmd, vmf->address);
+ ptep = pte_offset_map_nolock(vma->vm_mm, vmf->pmd, vmf->address,
+ &vmf->ptl);
if (unlikely(!ptep))
return VM_FAULT_NOPAGE;
@@ -3472,7 +3473,7 @@ static struct folio *next_uptodate_folio(struct xa_state *xas,
continue;
if (folio_test_locked(folio))
continue;
- if (!folio_try_get_rcu(folio))
+ if (!folio_try_get(folio))
continue;
/* Has the page moved or been split? */
if (unlikely(folio != xas_reload(xas)))
@@ -4248,6 +4249,9 @@ static void filemap_cachestat(struct address_space *mapping,
XA_STATE(xas, &mapping->i_pages, first_index);
struct folio *folio;
+ /* Flush stats (and potentially sleep) outside the RCU read section. */
+ mem_cgroup_flush_stats_ratelimited(NULL);
+
rcu_read_lock();
xas_for_each(&xas, folio, last_index) {
int order;
@@ -4311,7 +4315,7 @@ static void filemap_cachestat(struct address_space *mapping,
goto resched;
}
#endif
- if (workingset_test_recent(shadow, true, &workingset))
+ if (workingset_test_recent(shadow, true, &workingset, false))
cs->nr_recently_evicted += nr_pages;
goto resched;
diff --git a/mm/gup.c b/mm/gup.c
index ca0f5cedce9b..f1d6bc06eb52 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -76,7 +76,7 @@ retry:
folio = page_folio(page);
if (WARN_ON_ONCE(folio_ref_count(folio) < 0))
return NULL;
- if (unlikely(!folio_ref_try_add_rcu(folio, refs)))
+ if (unlikely(!folio_ref_try_add(folio, refs)))
return NULL;
/*
@@ -97,95 +97,6 @@ retry:
return folio;
}
-/**
- * try_grab_folio() - Attempt to get or pin a folio.
- * @page: pointer to page to be grabbed
- * @refs: the value to (effectively) add to the folio's refcount
- * @flags: gup flags: these are the FOLL_* flag values.
- *
- * "grab" names in this file mean, "look at flags to decide whether to use
- * FOLL_PIN or FOLL_GET behavior, when incrementing the folio's refcount.
- *
- * Either FOLL_PIN or FOLL_GET (or neither) must be set, but not both at the
- * same time. (That's true throughout the get_user_pages*() and
- * pin_user_pages*() APIs.) Cases:
- *
- * FOLL_GET: folio's refcount will be incremented by @refs.
- *
- * FOLL_PIN on large folios: folio's refcount will be incremented by
- * @refs, and its pincount will be incremented by @refs.
- *
- * FOLL_PIN on single-page folios: folio's refcount will be incremented by
- * @refs * GUP_PIN_COUNTING_BIAS.
- *
- * Return: The folio containing @page (with refcount appropriately
- * incremented) for success, or NULL upon failure. If neither FOLL_GET
- * nor FOLL_PIN was set, that's considered failure, and furthermore,
- * a likely bug in the caller, so a warning is also emitted.
- */
-struct folio *try_grab_folio(struct page *page, int refs, unsigned int flags)
-{
- struct folio *folio;
-
- if (WARN_ON_ONCE((flags & (FOLL_GET | FOLL_PIN)) == 0))
- return NULL;
-
- if (unlikely(!(flags & FOLL_PCI_P2PDMA) && is_pci_p2pdma_page(page)))
- return NULL;
-
- if (flags & FOLL_GET)
- return try_get_folio(page, refs);
-
- /* FOLL_PIN is set */
-
- /*
- * Don't take a pin on the zero page - it's not going anywhere
- * and it is used in a *lot* of places.
- */
- if (is_zero_page(page))
- return page_folio(page);
-
- folio = try_get_folio(page, refs);
- if (!folio)
- return NULL;
-
- /*
- * Can't do FOLL_LONGTERM + FOLL_PIN gup fast path if not in a
- * right zone, so fail and let the caller fall back to the slow
- * path.
- */
- if (unlikely((flags & FOLL_LONGTERM) &&
- !folio_is_longterm_pinnable(folio))) {
- if (!put_devmap_managed_folio_refs(folio, refs))
- folio_put_refs(folio, refs);
- return NULL;
- }
-
- /*
- * When pinning a large folio, use an exact count to track it.
- *
- * However, be sure to *also* increment the normal folio
- * refcount field at least once, so that the folio really
- * is pinned. That's why the refcount from the earlier
- * try_get_folio() is left intact.
- */
- if (folio_test_large(folio))
- atomic_add(refs, &folio->_pincount);
- else
- folio_ref_add(folio,
- refs * (GUP_PIN_COUNTING_BIAS - 1));
- /*
- * Adjust the pincount before re-checking the PTE for changes.
- * This is essentially a smp_mb() and is paired with a memory
- * barrier in folio_try_share_anon_rmap_*().
- */
- smp_mb__after_atomic();
-
- node_stat_mod_folio(folio, NR_FOLL_PIN_ACQUIRED, refs);
-
- return folio;
-}
-
static void gup_put_folio(struct folio *folio, int refs, unsigned int flags)
{
if (flags & FOLL_PIN) {
@@ -203,58 +114,59 @@ static void gup_put_folio(struct folio *folio, int refs, unsigned int flags)
}
/**
- * try_grab_page() - elevate a page's refcount by a flag-dependent amount
- * @page: pointer to page to be grabbed
- * @flags: gup flags: these are the FOLL_* flag values.
+ * try_grab_folio() - add a folio's refcount by a flag-dependent amount
+ * @folio: pointer to folio to be grabbed
+ * @refs: the value to (effectively) add to the folio's refcount
+ * @flags: gup flags: these are the FOLL_* flag values
*
* This might not do anything at all, depending on the flags argument.
*
* "grab" names in this file mean, "look at flags to decide whether to use
- * FOLL_PIN or FOLL_GET behavior, when incrementing the page's refcount.
+ * FOLL_PIN or FOLL_GET behavior, when incrementing the folio's refcount.
*
* Either FOLL_PIN or FOLL_GET (or neither) may be set, but not both at the same
- * time. Cases: please see the try_grab_folio() documentation, with
- * "refs=1".
+ * time.
*
* Return: 0 for success, or if no action was required (if neither FOLL_PIN
* nor FOLL_GET was set, nothing is done). A negative error code for failure:
*
- * -ENOMEM FOLL_GET or FOLL_PIN was set, but the page could not
+ * -ENOMEM FOLL_GET or FOLL_PIN was set, but the folio could not
* be grabbed.
+ *
+ * It is called when we have a stable reference for the folio, typically in
+ * GUP slow path.
*/
-int __must_check try_grab_page(struct page *page, unsigned int flags)
+int __must_check try_grab_folio(struct folio *folio, int refs,
+ unsigned int flags)
{
- struct folio *folio = page_folio(page);
-
if (WARN_ON_ONCE(folio_ref_count(folio) <= 0))
return -ENOMEM;
- if (unlikely(!(flags & FOLL_PCI_P2PDMA) && is_pci_p2pdma_page(page)))
+ if (unlikely(!(flags & FOLL_PCI_P2PDMA) && is_pci_p2pdma_page(&folio->page)))
return -EREMOTEIO;
if (flags & FOLL_GET)
- folio_ref_inc(folio);
+ folio_ref_add(folio, refs);
else if (flags & FOLL_PIN) {
/*
* Don't take a pin on the zero page - it's not going anywhere
* and it is used in a *lot* of places.
*/
- if (is_zero_page(page))
+ if (is_zero_folio(folio))
return 0;
/*
- * Similar to try_grab_folio(): be sure to *also*
- * increment the normal page refcount field at least once,
+ * Increment the normal page refcount field at least once,
* so that the page really is pinned.
*/
if (folio_test_large(folio)) {
- folio_ref_add(folio, 1);
- atomic_add(1, &folio->_pincount);
+ folio_ref_add(folio, refs);
+ atomic_add(refs, &folio->_pincount);
} else {
- folio_ref_add(folio, GUP_PIN_COUNTING_BIAS);
+ folio_ref_add(folio, refs * GUP_PIN_COUNTING_BIAS);
}
- node_stat_mod_folio(folio, NR_FOLL_PIN_ACQUIRED, 1);
+ node_stat_mod_folio(folio, NR_FOLL_PIN_ACQUIRED, refs);
}
return 0;
@@ -515,6 +427,102 @@ static int record_subpages(struct page *page, unsigned long sz,
return nr;
}
+
+/**
+ * try_grab_folio_fast() - Attempt to get or pin a folio in fast path.
+ * @page: pointer to page to be grabbed
+ * @refs: the value to (effectively) add to the folio's refcount
+ * @flags: gup flags: these are the FOLL_* flag values.
+ *
+ * "grab" names in this file mean, "look at flags to decide whether to use
+ * FOLL_PIN or FOLL_GET behavior, when incrementing the folio's refcount.
+ *
+ * Either FOLL_PIN or FOLL_GET (or neither) must be set, but not both at the
+ * same time. (That's true throughout the get_user_pages*() and
+ * pin_user_pages*() APIs.) Cases:
+ *
+ * FOLL_GET: folio's refcount will be incremented by @refs.
+ *
+ * FOLL_PIN on large folios: folio's refcount will be incremented by
+ * @refs, and its pincount will be incremented by @refs.
+ *
+ * FOLL_PIN on single-page folios: folio's refcount will be incremented by
+ * @refs * GUP_PIN_COUNTING_BIAS.
+ *
+ * Return: The folio containing @page (with refcount appropriately
+ * incremented) for success, or NULL upon failure. If neither FOLL_GET
+ * nor FOLL_PIN was set, that's considered failure, and furthermore,
+ * a likely bug in the caller, so a warning is also emitted.
+ *
+ * It uses add ref unless zero to elevate the folio refcount and must be called
+ * in fast path only.
+ */
+static struct folio *try_grab_folio_fast(struct page *page, int refs,
+ unsigned int flags)
+{
+ struct folio *folio;
+
+ /* Raise warn if it is not called in fast GUP */
+ VM_WARN_ON_ONCE(!irqs_disabled());
+
+ if (WARN_ON_ONCE((flags & (FOLL_GET | FOLL_PIN)) == 0))
+ return NULL;
+
+ if (unlikely(!(flags & FOLL_PCI_P2PDMA) && is_pci_p2pdma_page(page)))
+ return NULL;
+
+ if (flags & FOLL_GET)
+ return try_get_folio(page, refs);
+
+ /* FOLL_PIN is set */
+
+ /*
+ * Don't take a pin on the zero page - it's not going anywhere
+ * and it is used in a *lot* of places.
+ */
+ if (is_zero_page(page))
+ return page_folio(page);
+
+ folio = try_get_folio(page, refs);
+ if (!folio)
+ return NULL;
+
+ /*
+ * Can't do FOLL_LONGTERM + FOLL_PIN gup fast path if not in a
+ * right zone, so fail and let the caller fall back to the slow
+ * path.
+ */
+ if (unlikely((flags & FOLL_LONGTERM) &&
+ !folio_is_longterm_pinnable(folio))) {
+ if (!put_devmap_managed_folio_refs(folio, refs))
+ folio_put_refs(folio, refs);
+ return NULL;
+ }
+
+ /*
+ * When pinning a large folio, use an exact count to track it.
+ *
+ * However, be sure to *also* increment the normal folio
+ * refcount field at least once, so that the folio really
+ * is pinned. That's why the refcount from the earlier
+ * try_get_folio() is left intact.
+ */
+ if (folio_test_large(folio))
+ atomic_add(refs, &folio->_pincount);
+ else
+ folio_ref_add(folio,
+ refs * (GUP_PIN_COUNTING_BIAS - 1));
+ /*
+ * Adjust the pincount before re-checking the PTE for changes.
+ * This is essentially a smp_mb() and is paired with a memory
+ * barrier in folio_try_share_anon_rmap_*().
+ */
+ smp_mb__after_atomic();
+
+ node_stat_mod_folio(folio, NR_FOLL_PIN_ACQUIRED, refs);
+
+ return folio;
+}
#endif /* CONFIG_ARCH_HAS_HUGEPD || CONFIG_HAVE_GUP_FAST */
#ifdef CONFIG_ARCH_HAS_HUGEPD
@@ -535,7 +543,7 @@ static unsigned long hugepte_addr_end(unsigned long addr, unsigned long end,
*/
static int gup_hugepte(struct vm_area_struct *vma, pte_t *ptep, unsigned long sz,
unsigned long addr, unsigned long end, unsigned int flags,
- struct page **pages, int *nr)
+ struct page **pages, int *nr, bool fast)
{
unsigned long pte_end;
struct page *page;
@@ -558,9 +566,15 @@ static int gup_hugepte(struct vm_area_struct *vma, pte_t *ptep, unsigned long sz
page = pte_page(pte);
refs = record_subpages(page, sz, addr, end, pages + *nr);
- folio = try_grab_folio(page, refs, flags);
- if (!folio)
- return 0;
+ if (fast) {
+ folio = try_grab_folio_fast(page, refs, flags);
+ if (!folio)
+ return 0;
+ } else {
+ folio = page_folio(page);
+ if (try_grab_folio(folio, refs, flags))
+ return 0;
+ }
if (unlikely(pte_val(pte) != pte_val(ptep_get(ptep)))) {
gup_put_folio(folio, refs, flags);
@@ -588,7 +602,7 @@ static int gup_hugepte(struct vm_area_struct *vma, pte_t *ptep, unsigned long sz
static int gup_hugepd(struct vm_area_struct *vma, hugepd_t hugepd,
unsigned long addr, unsigned int pdshift,
unsigned long end, unsigned int flags,
- struct page **pages, int *nr)
+ struct page **pages, int *nr, bool fast)
{
pte_t *ptep;
unsigned long sz = 1UL << hugepd_shift(hugepd);
@@ -598,7 +612,8 @@ static int gup_hugepd(struct vm_area_struct *vma, hugepd_t hugepd,
ptep = hugepte_offset(hugepd, addr, pdshift);
do {
next = hugepte_addr_end(addr, end, sz);
- ret = gup_hugepte(vma, ptep, sz, addr, end, flags, pages, nr);
+ ret = gup_hugepte(vma, ptep, sz, addr, end, flags, pages, nr,
+ fast);
if (ret != 1)
return ret;
} while (ptep++, addr = next, addr != end);
@@ -625,7 +640,7 @@ static struct page *follow_hugepd(struct vm_area_struct *vma, hugepd_t hugepd,
ptep = hugepte_offset(hugepd, addr, pdshift);
ptl = huge_pte_lock(h, vma->vm_mm, ptep);
ret = gup_hugepd(vma, hugepd, addr, pdshift, addr + PAGE_SIZE,
- flags, &page, &nr);
+ flags, &page, &nr, false);
spin_unlock(ptl);
if (ret == 1) {
@@ -642,7 +657,7 @@ static struct page *follow_hugepd(struct vm_area_struct *vma, hugepd_t hugepd,
static inline int gup_hugepd(struct vm_area_struct *vma, hugepd_t hugepd,
unsigned long addr, unsigned int pdshift,
unsigned long end, unsigned int flags,
- struct page **pages, int *nr)
+ struct page **pages, int *nr, bool fast)
{
return 0;
}
@@ -729,7 +744,7 @@ static struct page *follow_huge_pud(struct vm_area_struct *vma,
gup_must_unshare(vma, flags, page))
return ERR_PTR(-EMLINK);
- ret = try_grab_page(page, flags);
+ ret = try_grab_folio(page_folio(page), 1, flags);
if (ret)
page = ERR_PTR(ret);
else
@@ -806,7 +821,7 @@ static struct page *follow_huge_pmd(struct vm_area_struct *vma,
VM_BUG_ON_PAGE((flags & FOLL_PIN) && PageAnon(page) &&
!PageAnonExclusive(page), page);
- ret = try_grab_page(page, flags);
+ ret = try_grab_folio(page_folio(page), 1, flags);
if (ret)
return ERR_PTR(ret);
@@ -968,8 +983,8 @@ static struct page *follow_page_pte(struct vm_area_struct *vma,
VM_BUG_ON_PAGE((flags & FOLL_PIN) && PageAnon(page) &&
!PageAnonExclusive(page), page);
- /* try_grab_page() does nothing unless FOLL_GET or FOLL_PIN is set. */
- ret = try_grab_page(page, flags);
+ /* try_grab_folio() does nothing unless FOLL_GET or FOLL_PIN is set. */
+ ret = try_grab_folio(page_folio(page), 1, flags);
if (unlikely(ret)) {
page = ERR_PTR(ret);
goto out;
@@ -1233,7 +1248,7 @@ static int get_gate_page(struct mm_struct *mm, unsigned long address,
goto unmap;
*page = pte_page(entry);
}
- ret = try_grab_page(*page, gup_flags);
+ ret = try_grab_folio(page_folio(*page), 1, gup_flags);
if (unlikely(ret))
goto unmap;
out:
@@ -1636,20 +1651,19 @@ next_page:
* pages.
*/
if (page_increm > 1) {
- struct folio *folio;
+ struct folio *folio = page_folio(page);
/*
* Since we already hold refcount on the
* large folio, this should never fail.
*/
- folio = try_grab_folio(page, page_increm - 1,
- foll_flags);
- if (WARN_ON_ONCE(!folio)) {
+ if (try_grab_folio(folio, page_increm - 1,
+ foll_flags)) {
/*
* Release the 1st page ref if the
* folio is problematic, fail hard.
*/
- gup_put_folio(page_folio(page), 1,
+ gup_put_folio(folio, 1,
foll_flags);
ret = -EFAULT;
goto out;
@@ -2797,7 +2811,6 @@ EXPORT_SYMBOL(get_user_pages_unlocked);
* This code is based heavily on the PowerPC implementation by Nick Piggin.
*/
#ifdef CONFIG_HAVE_GUP_FAST
-
/*
* Used in the GUP-fast path to determine whether GUP is permitted to work on
* a specific folio.
@@ -2962,7 +2975,7 @@ static int gup_fast_pte_range(pmd_t pmd, pmd_t *pmdp, unsigned long addr,
VM_BUG_ON(!pfn_valid(pte_pfn(pte)));
page = pte_page(pte);
- folio = try_grab_folio(page, 1, flags);
+ folio = try_grab_folio_fast(page, 1, flags);
if (!folio)
goto pte_unmap;
@@ -3049,7 +3062,7 @@ static int gup_fast_devmap_leaf(unsigned long pfn, unsigned long addr,
break;
}
- folio = try_grab_folio(page, 1, flags);
+ folio = try_grab_folio_fast(page, 1, flags);
if (!folio) {
gup_fast_undo_dev_pagemap(nr, nr_start, flags, pages);
break;
@@ -3138,7 +3151,7 @@ static int gup_fast_pmd_leaf(pmd_t orig, pmd_t *pmdp, unsigned long addr,
page = pmd_page(orig);
refs = record_subpages(page, PMD_SIZE, addr, end, pages + *nr);
- folio = try_grab_folio(page, refs, flags);
+ folio = try_grab_folio_fast(page, refs, flags);
if (!folio)
return 0;
@@ -3182,7 +3195,7 @@ static int gup_fast_pud_leaf(pud_t orig, pud_t *pudp, unsigned long addr,
page = pud_page(orig);
refs = record_subpages(page, PUD_SIZE, addr, end, pages + *nr);
- folio = try_grab_folio(page, refs, flags);
+ folio = try_grab_folio_fast(page, refs, flags);
if (!folio)
return 0;
@@ -3222,7 +3235,7 @@ static int gup_fast_pgd_leaf(pgd_t orig, pgd_t *pgdp, unsigned long addr,
page = pgd_page(orig);
refs = record_subpages(page, PGDIR_SIZE, addr, end, pages + *nr);
- folio = try_grab_folio(page, refs, flags);
+ folio = try_grab_folio_fast(page, refs, flags);
if (!folio)
return 0;
@@ -3276,7 +3289,8 @@ static int gup_fast_pmd_range(pud_t *pudp, pud_t pud, unsigned long addr,
* pmd format and THP pmd format
*/
if (gup_hugepd(NULL, __hugepd(pmd_val(pmd)), addr,
- PMD_SHIFT, next, flags, pages, nr) != 1)
+ PMD_SHIFT, next, flags, pages, nr,
+ true) != 1)
return 0;
} else if (!gup_fast_pte_range(pmd, pmdp, addr, next, flags,
pages, nr))
@@ -3306,7 +3320,8 @@ static int gup_fast_pud_range(p4d_t *p4dp, p4d_t p4d, unsigned long addr,
return 0;
} else if (unlikely(is_hugepd(__hugepd(pud_val(pud))))) {
if (gup_hugepd(NULL, __hugepd(pud_val(pud)), addr,
- PUD_SHIFT, next, flags, pages, nr) != 1)
+ PUD_SHIFT, next, flags, pages, nr,
+ true) != 1)
return 0;
} else if (!gup_fast_pmd_range(pudp, pud, addr, next, flags,
pages, nr))
@@ -3333,7 +3348,8 @@ static int gup_fast_p4d_range(pgd_t *pgdp, pgd_t pgd, unsigned long addr,
BUILD_BUG_ON(p4d_leaf(p4d));
if (unlikely(is_hugepd(__hugepd(p4d_val(p4d))))) {
if (gup_hugepd(NULL, __hugepd(p4d_val(p4d)), addr,
- P4D_SHIFT, next, flags, pages, nr) != 1)
+ P4D_SHIFT, next, flags, pages, nr,
+ true) != 1)
return 0;
} else if (!gup_fast_pud_range(p4dp, p4d, addr, next, flags,
pages, nr))
@@ -3362,7 +3378,8 @@ static void gup_fast_pgd_range(unsigned long addr, unsigned long end,
return;
} else if (unlikely(is_hugepd(__hugepd(pgd_val(pgd))))) {
if (gup_hugepd(NULL, __hugepd(pgd_val(pgd)), addr,
- PGDIR_SHIFT, next, flags, pages, nr) != 1)
+ PGDIR_SHIFT, next, flags, pages, nr,
+ true) != 1)
return;
} else if (!gup_fast_p4d_range(pgdp, pgd, addr, next, flags,
pages, nr))
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index db7946a0a28c..2120f7478e55 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -1331,7 +1331,7 @@ struct page *follow_devmap_pmd(struct vm_area_struct *vma, unsigned long addr,
if (!*pgmap)
return ERR_PTR(-EFAULT);
page = pfn_to_page(pfn);
- ret = try_grab_page(page, flags);
+ ret = try_grab_folio(page_folio(page), 1, flags);
if (ret)
page = ERR_PTR(ret);
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index f35abff8be60..43e1af868cfd 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1625,13 +1625,10 @@ static inline void destroy_compound_gigantic_folio(struct folio *folio,
* folio appears as just a compound page. Otherwise, wait until after
* allocating vmemmap to clear the flag.
*
- * A reference is held on the folio, except in the case of demote.
- *
* Must be called with hugetlb lock held.
*/
-static void __remove_hugetlb_folio(struct hstate *h, struct folio *folio,
- bool adjust_surplus,
- bool demote)
+static void remove_hugetlb_folio(struct hstate *h, struct folio *folio,
+ bool adjust_surplus)
{
int nid = folio_nid(folio);
@@ -1645,6 +1642,7 @@ static void __remove_hugetlb_folio(struct hstate *h, struct folio *folio,
list_del(&folio->lru);
if (folio_test_hugetlb_freed(folio)) {
+ folio_clear_hugetlb_freed(folio);
h->free_huge_pages--;
h->free_huge_pages_node[nid]--;
}
@@ -1661,33 +1659,13 @@ static void __remove_hugetlb_folio(struct hstate *h, struct folio *folio,
if (!folio_test_hugetlb_vmemmap_optimized(folio))
__folio_clear_hugetlb(folio);
- /*
- * In the case of demote we do not ref count the page as it will soon
- * be turned into a page of smaller size.
- */
- if (!demote)
- folio_ref_unfreeze(folio, 1);
-
h->nr_huge_pages--;
h->nr_huge_pages_node[nid]--;
}
-static void remove_hugetlb_folio(struct hstate *h, struct folio *folio,
- bool adjust_surplus)
-{
- __remove_hugetlb_folio(h, folio, adjust_surplus, false);
-}
-
-static void remove_hugetlb_folio_for_demote(struct hstate *h, struct folio *folio,
- bool adjust_surplus)
-{
- __remove_hugetlb_folio(h, folio, adjust_surplus, true);
-}
-
static void add_hugetlb_folio(struct hstate *h, struct folio *folio,
bool adjust_surplus)
{
- int zeroed;
int nid = folio_nid(folio);
VM_BUG_ON_FOLIO(!folio_test_hugetlb_vmemmap_optimized(folio), folio);
@@ -1711,21 +1689,6 @@ static void add_hugetlb_folio(struct hstate *h, struct folio *folio,
*/
folio_set_hugetlb_vmemmap_optimized(folio);
- /*
- * This folio is about to be managed by the hugetlb allocator and
- * should have no users. Drop our reference, and check for others
- * just in case.
- */
- zeroed = folio_put_testzero(folio);
- if (unlikely(!zeroed))
- /*
- * It is VERY unlikely soneone else has taken a ref
- * on the folio. In this case, we simply return as
- * free_huge_folio() will be called when this other ref
- * is dropped.
- */
- return;
-
arch_clear_hugetlb_flags(folio);
enqueue_hugetlb_folio(h, folio);
}
@@ -1763,13 +1726,6 @@ static void __update_and_free_hugetlb_folio(struct hstate *h,
}
/*
- * Move PageHWPoison flag from head page to the raw error pages,
- * which makes any healthy subpages reusable.
- */
- if (unlikely(folio_test_hwpoison(folio)))
- folio_clear_hugetlb_hwpoison(folio);
-
- /*
* If vmemmap pages were allocated above, then we need to clear the
* hugetlb flag under the hugetlb lock.
*/
@@ -1780,6 +1736,15 @@ static void __update_and_free_hugetlb_folio(struct hstate *h,
}
/*
+ * Move PageHWPoison flag from head page to the raw error pages,
+ * which makes any healthy subpages reusable.
+ */
+ if (unlikely(folio_test_hwpoison(folio)))
+ folio_clear_hugetlb_hwpoison(folio);
+
+ folio_ref_unfreeze(folio, 1);
+
+ /*
* Non-gigantic pages demoted from CMA allocated gigantic pages
* need to be given back to CMA in free_gigantic_folio.
*/
@@ -2197,6 +2162,9 @@ static struct folio *alloc_buddy_hugetlb_folio(struct hstate *h,
nid = numa_mem_id();
retry:
folio = __folio_alloc(gfp_mask, order, nid, nmask);
+ /* Ensure hugetlb folio won't have large_rmappable flag set. */
+ if (folio)
+ folio_clear_large_rmappable(folio);
if (folio && !folio_ref_freeze(folio, 1)) {
folio_put(folio);
@@ -3079,11 +3047,8 @@ retry:
free_new:
spin_unlock_irq(&hugetlb_lock);
- if (new_folio) {
- /* Folio has a zero ref count, but needs a ref to be freed */
- folio_ref_unfreeze(new_folio, 1);
+ if (new_folio)
update_and_free_hugetlb_folio(h, new_folio, false);
- }
return ret;
}
@@ -3938,7 +3903,7 @@ static int demote_free_hugetlb_folio(struct hstate *h, struct folio *folio)
target_hstate = size_to_hstate(PAGE_SIZE << h->demote_order);
- remove_hugetlb_folio_for_demote(h, folio, false);
+ remove_hugetlb_folio(h, folio, false);
spin_unlock_irq(&hugetlb_lock);
/*
@@ -3952,7 +3917,6 @@ static int demote_free_hugetlb_folio(struct hstate *h, struct folio *folio)
if (rc) {
/* Allocation of vmemmmap failed, we can not demote folio */
spin_lock_irq(&hugetlb_lock);
- folio_ref_unfreeze(folio, 1);
add_hugetlb_folio(h, folio, false);
return rc;
}
diff --git a/mm/hugetlb_vmemmap.c b/mm/hugetlb_vmemmap.c
index b9a55322e52c..8193906515c6 100644
--- a/mm/hugetlb_vmemmap.c
+++ b/mm/hugetlb_vmemmap.c
@@ -446,6 +446,8 @@ static int __hugetlb_vmemmap_restore_folio(const struct hstate *h,
unsigned long vmemmap_reuse;
VM_WARN_ON_ONCE_FOLIO(!folio_test_hugetlb(folio), folio);
+ VM_WARN_ON_ONCE_FOLIO(folio_ref_count(folio), folio);
+
if (!folio_test_hugetlb_vmemmap_optimized(folio))
return 0;
@@ -481,6 +483,9 @@ static int __hugetlb_vmemmap_restore_folio(const struct hstate *h,
*/
int hugetlb_vmemmap_restore_folio(const struct hstate *h, struct folio *folio)
{
+ /* avoid writes from page_ref_add_unless() while unfolding vmemmap */
+ synchronize_rcu();
+
return __hugetlb_vmemmap_restore_folio(h, folio, 0);
}
@@ -505,6 +510,9 @@ long hugetlb_vmemmap_restore_folios(const struct hstate *h,
long restored = 0;
long ret = 0;
+ /* avoid writes from page_ref_add_unless() while unfolding vmemmap */
+ synchronize_rcu();
+
list_for_each_entry_safe(folio, t_folio, folio_list, lru) {
if (folio_test_hugetlb_vmemmap_optimized(folio)) {
ret = __hugetlb_vmemmap_restore_folio(h, folio,
@@ -550,6 +558,8 @@ static int __hugetlb_vmemmap_optimize_folio(const struct hstate *h,
unsigned long vmemmap_reuse;
VM_WARN_ON_ONCE_FOLIO(!folio_test_hugetlb(folio), folio);
+ VM_WARN_ON_ONCE_FOLIO(folio_ref_count(folio), folio);
+
if (!vmemmap_should_optimize_folio(h, folio))
return ret;
@@ -601,6 +611,9 @@ void hugetlb_vmemmap_optimize_folio(const struct hstate *h, struct folio *folio)
{
LIST_HEAD(vmemmap_pages);
+ /* avoid writes from page_ref_add_unless() while folding vmemmap */
+ synchronize_rcu();
+
__hugetlb_vmemmap_optimize_folio(h, folio, &vmemmap_pages, 0);
free_vmemmap_page_list(&vmemmap_pages);
}
@@ -644,6 +657,9 @@ void hugetlb_vmemmap_optimize_folios(struct hstate *h, struct list_head *folio_l
flush_tlb_all();
+ /* avoid writes from page_ref_add_unless() while folding vmemmap */
+ synchronize_rcu();
+
list_for_each_entry(folio, folio_list, lru) {
int ret;
diff --git a/mm/internal.h b/mm/internal.h
index 6902b7dd8509..cc2c5e07fad3 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -1182,8 +1182,8 @@ int migrate_device_coherent_page(struct page *page);
/*
* mm/gup.c
*/
-struct folio *try_grab_folio(struct page *page, int refs, unsigned int flags);
-int __must_check try_grab_page(struct page *page, unsigned int flags);
+int __must_check try_grab_folio(struct folio *folio, int refs,
+ unsigned int flags);
/*
* mm/huge_memory.c
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 71fe2a95b8bd..8f2f1bb18c9c 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -7823,17 +7823,6 @@ void mem_cgroup_migrate(struct folio *old, struct folio *new)
/* Transfer the charge and the css ref */
commit_charge(new, memcg);
- /*
- * If the old folio is a large folio and is in the split queue, it needs
- * to be removed from the split queue now, in case getting an incorrect
- * split queue in destroy_large_folio() after the memcg of the old folio
- * is cleared.
- *
- * In addition, the old folio is about to be freed after migration, so
- * removing from the split queue a bit earlier seems reasonable.
- */
- if (folio_test_large(old) && folio_test_large_rmappable(old))
- folio_undo_large_rmappable(old);
old->memcg_data = 0;
}
diff --git a/mm/migrate.c b/mm/migrate.c
index 20cb9f5f7446..a8c6f466e33a 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -415,6 +415,15 @@ int folio_migrate_mapping(struct address_space *mapping,
if (folio_ref_count(folio) != expected_count)
return -EAGAIN;
+ /* Take off deferred split queue while frozen and memcg set */
+ if (folio_test_large(folio) &&
+ folio_test_large_rmappable(folio)) {
+ if (!folio_ref_freeze(folio, expected_count))
+ return -EAGAIN;
+ folio_undo_large_rmappable(folio);
+ folio_ref_unfreeze(folio, expected_count);
+ }
+
/* No turning back from here */
newfolio->index = folio->index;
newfolio->mapping = folio->mapping;
@@ -433,6 +442,10 @@ int folio_migrate_mapping(struct address_space *mapping,
return -EAGAIN;
}
+ /* Take off deferred split queue while frozen and memcg set */
+ if (folio_test_large(folio) && folio_test_large_rmappable(folio))
+ folio_undo_large_rmappable(folio);
+
/*
* Now we know that no one else is looking at the folio:
* no turning back from here.
diff --git a/mm/readahead.c b/mm/readahead.c
index c1b23989d9ca..817b2a352d78 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -503,11 +503,11 @@ void page_cache_ra_order(struct readahead_control *ractl,
limit = min(limit, index + ra->size - 1);
- if (new_order < MAX_PAGECACHE_ORDER) {
+ if (new_order < MAX_PAGECACHE_ORDER)
new_order += 2;
- new_order = min_t(unsigned int, MAX_PAGECACHE_ORDER, new_order);
- new_order = min_t(unsigned int, new_order, ilog2(ra->size));
- }
+
+ new_order = min_t(unsigned int, MAX_PAGECACHE_ORDER, new_order);
+ new_order = min_t(unsigned int, new_order, ilog2(ra->size));
/* See comment in page_cache_ra_unbounded() */
nofs = memalloc_nofs_save();
diff --git a/mm/shmem.c b/mm/shmem.c
index a8b181a63402..c1befe046c7e 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -541,8 +541,9 @@ static bool shmem_confirm_swap(struct address_space *mapping,
static int shmem_huge __read_mostly = SHMEM_HUGE_NEVER;
-bool shmem_is_huge(struct inode *inode, pgoff_t index, bool shmem_huge_force,
- struct mm_struct *mm, unsigned long vm_flags)
+static bool __shmem_is_huge(struct inode *inode, pgoff_t index,
+ bool shmem_huge_force, struct mm_struct *mm,
+ unsigned long vm_flags)
{
loff_t i_size;
@@ -573,6 +574,16 @@ bool shmem_is_huge(struct inode *inode, pgoff_t index, bool shmem_huge_force,
}
}
+bool shmem_is_huge(struct inode *inode, pgoff_t index,
+ bool shmem_huge_force, struct mm_struct *mm,
+ unsigned long vm_flags)
+{
+ if (HPAGE_PMD_ORDER > MAX_PAGECACHE_ORDER)
+ return false;
+
+ return __shmem_is_huge(inode, index, shmem_huge_force, mm, vm_flags);
+}
+
#if defined(CONFIG_SYSFS)
static int shmem_parse_huge(const char *str)
{
diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index d0cbdd7c1e5b..e34ea860153f 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -2543,7 +2543,15 @@ static DEFINE_PER_CPU(struct vmap_block_queue, vmap_block_queue);
static struct xarray *
addr_to_vb_xa(unsigned long addr)
{
- int index = (addr / VMAP_BLOCK_SIZE) % num_possible_cpus();
+ int index = (addr / VMAP_BLOCK_SIZE) % nr_cpu_ids;
+
+ /*
+ * Please note, nr_cpu_ids points on a highest set
+ * possible bit, i.e. we never invoke cpumask_next()
+ * if an index points on it which is nr_cpu_ids - 1.
+ */
+ if (!cpu_possible(index))
+ index = cpumask_next(index, cpu_possible_mask);
return &per_cpu(vmap_block_queue, index).vmap_blocks;
}
diff --git a/mm/workingset.c b/mm/workingset.c
index c22adb93622a..a2b28e356e68 100644
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -412,10 +412,12 @@ void *workingset_eviction(struct folio *folio, struct mem_cgroup *target_memcg)
* @file: whether the corresponding folio is from the file lru.
* @workingset: where the workingset value unpacked from shadow should
* be stored.
+ * @flush: whether to flush cgroup rstat.
*
* Return: true if the shadow is for a recently evicted folio; false otherwise.
*/
-bool workingset_test_recent(void *shadow, bool file, bool *workingset)
+bool workingset_test_recent(void *shadow, bool file, bool *workingset,
+ bool flush)
{
struct mem_cgroup *eviction_memcg;
struct lruvec *eviction_lruvec;
@@ -467,10 +469,16 @@ bool workingset_test_recent(void *shadow, bool file, bool *workingset)
/*
* Flush stats (and potentially sleep) outside the RCU read section.
+ *
+ * Note that workingset_test_recent() itself might be called in RCU read
+ * section (for e.g, in cachestat) - these callers need to skip flushing
+ * stats (via the flush argument).
+ *
* XXX: With per-memcg flushing and thresholding, is ratelimiting
* still needed here?
*/
- mem_cgroup_flush_stats_ratelimited(eviction_memcg);
+ if (flush)
+ mem_cgroup_flush_stats_ratelimited(eviction_memcg);
eviction_lruvec = mem_cgroup_lruvec(eviction_memcg, pgdat);
refault = atomic_long_read(&eviction_lruvec->nonresident_age);
@@ -558,7 +566,7 @@ void workingset_refault(struct folio *folio, void *shadow)
mod_lruvec_state(lruvec, WORKINGSET_REFAULT_BASE + file, nr);
- if (!workingset_test_recent(shadow, file, &workingset))
+ if (!workingset_test_recent(shadow, file, &workingset, true))
return;
folio_set_active(folio);