Contributors: 30
| Author |
Tokens |
Token Proportion |
Commits |
Commit Proportion |
| Fengguang Wu |
340 |
26.34% |
5 |
7.46% |
| Matt Mackall |
166 |
12.86% |
2 |
2.99% |
| Alexey Dobriyan |
120 |
9.30% |
4 |
5.97% |
| Matthew Wilcox |
107 |
8.29% |
6 |
8.96% |
| Luiz Fernando N. Capitulino |
96 |
7.44% |
2 |
2.99% |
| Liu Ye |
95 |
7.36% |
1 |
1.49% |
| Linus Torvalds (pre-git) |
81 |
6.27% |
10 |
14.93% |
| David Hildenbrand |
80 |
6.20% |
6 |
8.96% |
| Vladimir Davydov |
58 |
4.49% |
4 |
5.97% |
| Yalin Wang |
34 |
2.63% |
1 |
1.49% |
| Naoya Horiguchi |
19 |
1.47% |
3 |
4.48% |
| Hugh Dickins |
17 |
1.32% |
2 |
2.99% |
| Andrea Arcangeli |
12 |
0.93% |
2 |
2.99% |
| Steven Price |
9 |
0.70% |
1 |
1.49% |
| Ran Xiaokai |
9 |
0.70% |
1 |
1.49% |
| Andrew Morton |
7 |
0.54% |
2 |
2.99% |
| Kirill A. Shutemov |
6 |
0.46% |
1 |
1.49% |
| Vivek Goyal |
5 |
0.39% |
1 |
1.49% |
| Peter Collingbourne |
5 |
0.39% |
1 |
1.49% |
| Konstantin Khlebnikov |
4 |
0.31% |
1 |
1.49% |
| Linus Torvalds |
4 |
0.31% |
2 |
2.99% |
| Andries E. Brouwer |
4 |
0.31% |
1 |
1.49% |
| David Howells |
3 |
0.23% |
1 |
1.49% |
| Dan J Williams |
3 |
0.23% |
1 |
1.49% |
| Motohiro Kosaki |
2 |
0.15% |
1 |
1.49% |
| Mike Rapoport |
1 |
0.08% |
1 |
1.49% |
| Greg Kroah-Hartman |
1 |
0.08% |
1 |
1.49% |
| Paul Gortmaker |
1 |
0.08% |
1 |
1.49% |
| SeongJae Park |
1 |
0.08% |
1 |
1.49% |
| Thomas Tuttle |
1 |
0.08% |
1 |
1.49% |
| Total |
1291 |
|
67 |
|
// SPDX-License-Identifier: GPL-2.0
#include <linux/memblock.h>
#include <linux/compiler.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/ksm.h>
#include <linux/mm.h>
#include <linux/mmzone.h>
#include <linux/huge_mm.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/hugetlb.h>
#include <linux/memremap.h>
#include <linux/memcontrol.h>
#include <linux/mmu_notifier.h>
#include <linux/page_idle.h>
#include <linux/kernel-page-flags.h>
#include <linux/uaccess.h>
#include "internal.h"
#define KPMSIZE sizeof(u64)
#define KPMMASK (KPMSIZE - 1)
#define KPMBITS (KPMSIZE * BITS_PER_BYTE)
enum kpage_operation {
KPAGE_FLAGS,
KPAGE_COUNT,
KPAGE_CGROUP,
};
static inline unsigned long get_max_dump_pfn(void)
{
#ifdef CONFIG_SPARSEMEM
/*
* The memmap of early sections is completely populated and marked
* online even if max_pfn does not fall on a section boundary -
* pfn_to_online_page() will succeed on all pages. Allow inspecting
* these memmaps.
*/
return round_up(max_pfn, PAGES_PER_SECTION);
#else
return max_pfn;
#endif
}
static u64 get_kpage_count(const struct page *page)
{
struct page_snapshot ps;
u64 ret;
snapshot_page(&ps, page);
if (IS_ENABLED(CONFIG_PAGE_MAPCOUNT))
ret = folio_precise_page_mapcount(&ps.folio_snapshot,
&ps.page_snapshot);
else
ret = folio_average_page_mapcount(&ps.folio_snapshot);
return ret;
}
static ssize_t kpage_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos,
enum kpage_operation op)
{
const unsigned long max_dump_pfn = get_max_dump_pfn();
u64 __user *out = (u64 __user *)buf;
struct page *page;
unsigned long src = *ppos;
unsigned long pfn;
ssize_t ret = 0;
u64 info;
pfn = src / KPMSIZE;
if (src & KPMMASK || count & KPMMASK)
return -EINVAL;
if (src >= max_dump_pfn * KPMSIZE)
return 0;
count = min_t(unsigned long, count, (max_dump_pfn * KPMSIZE) - src);
while (count > 0) {
/*
* TODO: ZONE_DEVICE support requires to identify
* memmaps that were actually initialized.
*/
page = pfn_to_online_page(pfn);
if (page) {
switch (op) {
case KPAGE_FLAGS:
info = stable_page_flags(page);
break;
case KPAGE_COUNT:
info = get_kpage_count(page);
break;
case KPAGE_CGROUP:
info = page_cgroup_ino(page);
break;
default:
info = 0;
break;
}
} else
info = 0;
if (put_user(info, out)) {
ret = -EFAULT;
break;
}
pfn++;
out++;
count -= KPMSIZE;
cond_resched();
}
*ppos += (char __user *)out - buf;
if (!ret)
ret = (char __user *)out - buf;
return ret;
}
/* /proc/kpagecount - an array exposing page mapcounts
*
* Each entry is a u64 representing the corresponding
* physical page mapcount.
*/
static ssize_t kpagecount_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
return kpage_read(file, buf, count, ppos, KPAGE_COUNT);
}
static const struct proc_ops kpagecount_proc_ops = {
.proc_flags = PROC_ENTRY_PERMANENT,
.proc_lseek = mem_lseek,
.proc_read = kpagecount_read,
};
static inline u64 kpf_copy_bit(u64 kflags, int ubit, int kbit)
{
return ((kflags >> kbit) & 1) << ubit;
}
u64 stable_page_flags(const struct page *page)
{
const struct folio *folio;
struct page_snapshot ps;
unsigned long k;
unsigned long mapping;
bool is_anon;
u64 u = 0;
/*
* pseudo flag: KPF_NOPAGE
* it differentiates a memory hole from a page with no flags
*/
if (!page)
return 1 << KPF_NOPAGE;
snapshot_page(&ps, page);
folio = &ps.folio_snapshot;
k = folio->flags;
mapping = (unsigned long)folio->mapping;
is_anon = mapping & FOLIO_MAPPING_ANON;
/*
* pseudo flags for the well known (anonymous) memory mapped pages
*/
if (folio_mapped(folio))
u |= 1 << KPF_MMAP;
if (is_anon) {
u |= 1 << KPF_ANON;
if (mapping & FOLIO_MAPPING_KSM)
u |= 1 << KPF_KSM;
}
/*
* compound pages: export both head/tail info
* they together define a compound page's start/end pos and order
*/
if (ps.idx == 0)
u |= kpf_copy_bit(k, KPF_COMPOUND_HEAD, PG_head);
else
u |= 1 << KPF_COMPOUND_TAIL;
if (folio_test_hugetlb(folio))
u |= 1 << KPF_HUGE;
else if (folio_test_large(folio) &&
folio_test_large_rmappable(folio)) {
/* Note: we indicate any THPs here, not just PMD-sized ones */
u |= 1 << KPF_THP;
} else if (is_huge_zero_pfn(ps.pfn)) {
u |= 1 << KPF_ZERO_PAGE;
u |= 1 << KPF_THP;
} else if (is_zero_pfn(ps.pfn)) {
u |= 1 << KPF_ZERO_PAGE;
}
if (ps.flags & PAGE_SNAPSHOT_PG_BUDDY)
u |= 1 << KPF_BUDDY;
if (folio_test_offline(folio))
u |= 1 << KPF_OFFLINE;
if (folio_test_pgtable(folio))
u |= 1 << KPF_PGTABLE;
if (folio_test_slab(folio))
u |= 1 << KPF_SLAB;
#if defined(CONFIG_PAGE_IDLE_FLAG) && defined(CONFIG_64BIT)
u |= kpf_copy_bit(k, KPF_IDLE, PG_idle);
#else
if (ps.flags & PAGE_SNAPSHOT_PG_IDLE)
u |= 1 << KPF_IDLE;
#endif
u |= kpf_copy_bit(k, KPF_LOCKED, PG_locked);
u |= kpf_copy_bit(k, KPF_DIRTY, PG_dirty);
u |= kpf_copy_bit(k, KPF_UPTODATE, PG_uptodate);
u |= kpf_copy_bit(k, KPF_WRITEBACK, PG_writeback);
u |= kpf_copy_bit(k, KPF_LRU, PG_lru);
u |= kpf_copy_bit(k, KPF_REFERENCED, PG_referenced);
u |= kpf_copy_bit(k, KPF_ACTIVE, PG_active);
u |= kpf_copy_bit(k, KPF_RECLAIM, PG_reclaim);
#define SWAPCACHE ((1 << PG_swapbacked) | (1 << PG_swapcache))
if ((k & SWAPCACHE) == SWAPCACHE)
u |= 1 << KPF_SWAPCACHE;
u |= kpf_copy_bit(k, KPF_SWAPBACKED, PG_swapbacked);
u |= kpf_copy_bit(k, KPF_UNEVICTABLE, PG_unevictable);
u |= kpf_copy_bit(k, KPF_MLOCKED, PG_mlocked);
#ifdef CONFIG_MEMORY_FAILURE
if (u & (1 << KPF_HUGE))
u |= kpf_copy_bit(k, KPF_HWPOISON, PG_hwpoison);
else
u |= kpf_copy_bit(ps.page_snapshot.flags, KPF_HWPOISON, PG_hwpoison);
#endif
u |= kpf_copy_bit(k, KPF_RESERVED, PG_reserved);
u |= kpf_copy_bit(k, KPF_OWNER_2, PG_owner_2);
u |= kpf_copy_bit(k, KPF_PRIVATE, PG_private);
u |= kpf_copy_bit(k, KPF_PRIVATE_2, PG_private_2);
u |= kpf_copy_bit(k, KPF_OWNER_PRIVATE, PG_owner_priv_1);
u |= kpf_copy_bit(k, KPF_ARCH, PG_arch_1);
#ifdef CONFIG_ARCH_USES_PG_ARCH_2
u |= kpf_copy_bit(k, KPF_ARCH_2, PG_arch_2);
#endif
#ifdef CONFIG_ARCH_USES_PG_ARCH_3
u |= kpf_copy_bit(k, KPF_ARCH_3, PG_arch_3);
#endif
return u;
}
/* /proc/kpageflags - an array exposing page flags
*
* Each entry is a u64 representing the corresponding
* physical page flags.
*/
static ssize_t kpageflags_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
return kpage_read(file, buf, count, ppos, KPAGE_FLAGS);
}
static const struct proc_ops kpageflags_proc_ops = {
.proc_flags = PROC_ENTRY_PERMANENT,
.proc_lseek = mem_lseek,
.proc_read = kpageflags_read,
};
#ifdef CONFIG_MEMCG
static ssize_t kpagecgroup_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
return kpage_read(file, buf, count, ppos, KPAGE_CGROUP);
}
static const struct proc_ops kpagecgroup_proc_ops = {
.proc_flags = PROC_ENTRY_PERMANENT,
.proc_lseek = mem_lseek,
.proc_read = kpagecgroup_read,
};
#endif /* CONFIG_MEMCG */
static int __init proc_page_init(void)
{
proc_create("kpagecount", S_IRUSR, NULL, &kpagecount_proc_ops);
proc_create("kpageflags", S_IRUSR, NULL, &kpageflags_proc_ops);
#ifdef CONFIG_MEMCG
proc_create("kpagecgroup", S_IRUSR, NULL, &kpagecgroup_proc_ops);
#endif
return 0;
}
fs_initcall(proc_page_init);